Скрипт калькулятора:

Код:
<!-- HEAD START HERE -->


<style type="text/css">
<!--
body {font-family: helvetica}
p {font-size: 12pt}
.red {color: red}
.blue {color: blue}
-->
</style>

<SCRIPT LANGUAGE="JavaScript">
<!-- Original:  Evsikoff_Andrey -->
<!-- Web Site:  http://gsmevsikov.mybb.ru/ -->


<!-- Begin
var Memory = 0;
var Number1 = "";
var Number2 = "";
var NewNumber = "blank";
var opvalue = "";

function Display(displaynumber) {
document.calculator.answer.value = displaynumber;
}

function MemoryClear() {
Memory = 0;
document.calculator.mem.value = "";
}

function MemoryRecall(answer) {
if(NewNumber != "blank") {
Number2 += answer;
} else {
Number1 = answer;
}
NewNumber = "blank";
Display(answer);
}

function MemorySubtract(answer) {
Memory = Memory - eval(answer);
}

function MemoryAdd(answer) {
Memory = Memory + eval(answer);
document.calculator.mem.value = " M ";
NewNumber = "blank";
}

function ClearCalc() {
Number1 = "";
Number2 = "";
NewNumber = "blank";
Display("");
}

function Backspace(answer) {
answerlength = answer.length;
answer = answer.substring(0, answerlength - 1);
if (Number2 != "") {
Number2 = answer.toString();
Display(Number2);
} else {
Number1 = answer.toString();
Display(Number1);
   }
}

function CECalc() {
Number2 = "";
NewNumber = "yes";
Display("");
}

function CheckNumber(answer) {
if(answer == ".") {
Number = document.calculator.answer.value;
if(Number.indexOf(".") != -1) {
answer = "";
   }
}
if(NewNumber == "yes") {
Number2 += answer;
Display(Number2);
}
else {
if(NewNumber == "blank") {
Number1 = answer;
Number2 = "";
NewNumber = "no";
}
else {
Number1 += answer;
}
Display(Number1);
   }
}
function AddButton(x) {
if(x == 1) EqualButton();
if(Number2 != "") {
Number1 = parseFloat(Number1) + parseFloat(Number2);
}
NewNumber = "yes";
opvalue = '+';
Display(Number1);
}
function SubButton(x) {
if(x == 1) EqualButton();
if(Number2 != "") {
Number1 = parseFloat(Number1) - parseFloat(Number2);
}
NewNumber = "yes";
opvalue = '-';
Display(Number1);
}
function MultButton(x) {
if(x == 1) EqualButton();
if(Number2 != "") {
Number1 = parseFloat(Number1) * parseFloat(Number2);
}
NewNumber = "yes";
opvalue = '*';
Display(Number1);
}
function DivButton(x) {
if(x == 1) EqualButton();
if(Number2 != "") {
Number1 = parseFloat(Number1) / parseFloat(Number2);
}
NewNumber = "yes";
opvalue = '/';
Display(Number1);
}
function SqrtButton() {
Number1 = Math.sqrt(Number1);
NewNumber = "blank";
Display(Number1);
}
function PercentButton() {
if(NewNumber != "blank") {
Number2 *= .01;
NewNumber = "blank";
Display(Number2);
   }
}
function RecipButton() {
Number1 = 1/Number1;
NewNumber = "blank";
Display(Number1);
}
function NegateButton() {
Number1 = parseFloat(-Number1);
NewNumber = "no";
Display(Number1);
}
function EqualButton() {
if(opvalue == '+') AddButton(0);
if(opvalue == '-') SubButton(0);
if(opvalue == '*') MultButton(0);
if(opvalue == '/') DivButton(0);
Number2 = "";
opvalue = "";
}
//  End -->
</script>


<!-- HEAD END HERE -->




</head>
<body bgcolor="#EDEDED" text="#000000" link="#000000" topmargin="0" leftmargin="0">
<center>

<!-- BODY START HERE -->

<form name="calculator">
<table bgcolor="#aaaaaa" width=220>
<tr><td>
<table bgcolor="#cccccc" border=1>
<tr><td>
<table border=0 cellpadding=0>
<tr><td bgcolor="#000080"><b style="color:white">Calculator</b></td></tr>
<tr><td>
<table width="100%" border=0>
<tr><td colspan=6><input type="text" name="answer" size=30 maxlength=30 onChange="CheckNumber(this.value)"></td></tr>
<tr><td colspan=6>
<table border=0 cellpadding=0>
<tr><td>
<input type="text" name="mem" size=3 maxlength=3> <input type="button" name="backspace" class="red" value="Backspace" onClick="Backspace(document.calculator.answer.value); return false;"> <input type="button" name="CE" class="red" value=" CE " onClick="CECalc(); return false;"> <input type="reset" name="C" class="red" value="  C  " onClick="ClearCalc(); return false;">
</td></tr>
</table>
</td></tr>
<tr><td><input type="button" name="MC" class="red" value=" MC " onClick="MemoryClear(); return false;"></td>
<td><input type="button" name="calc7" class="blue" value="  7  " onClick="CheckNumber('7'); return false;"></td>
<td><input type="button" name="calc8" class="blue" value="  8  " onClick="CheckNumber('8'); return false;"></td>
<td><input type="button" name="calc9" class="blue" value="  9  " onClick="CheckNumber('9'); return false;"></td>
<td><input type="button" name="divide" class="red" value="  /  " onClick="DivButton(1); return false;"></td>
<td><input type="button" name="sqrt" class="blue" value="sqrt" onClick="SqrtButton(); return false;"></td></tr>
<tr><td><input type="button" name="MR" class="red" value=" MR " onClick="MemoryRecall(Memory); return false;"></td>
<td><input type="button" name="calc4" class="blue" value="  4  " onClick="CheckNumber('4'); return false;"></td>
<td><input type="button" name="calc5" class="blue" value="  5  " onClick="CheckNumber('5'); return false;"></td>
<td><input type="button" name="calc6" class="blue" value="  6  " onClick="CheckNumber('6'); return false;"></td>
<td><input type="button" name="multiply" class="red" value="  *  " onClick="MultButton(1); return false;"></td>
<td><input type="button" name="percent" class="blue" value=" %  " onClick="PercentButton(); return false;"></td></tr>
<tr><td><input type="button" name="MS" class="red" value=" MS " onClick="MemorySubtract(document.calculator.answer.value); return false;"></td>
<td><input type="button" name="calc1" class="blue" value="  1  " onClick="CheckNumber('1'); return false;"></td>
<td><input type="button" name="calc2" class="blue" value="  2  " onClick="CheckNumber('2'); return false;"></td>
<td><input type="button" name="calc3" class="blue" value="  3  " onClick="CheckNumber('3'); return false;"></td>
<td><input type="button" name="minus" class="red" value="  -  " onClick="SubButton(1); return false;"></td>
<td><input type="button" name="recip" class="blue" value="1/x " onClick="RecipButton(); return false;"></td></tr>
<tr><td><input type="button" name="Mplus" class="red" value=" M+  " onClick="MemoryAdd(document.calculator.answer.value); return false;"></td>
<td><input type="button" name="calc0" class="blue" value="  0  " onClick="CheckNumber('0'); return false;"></td>
<td><input type="button" name="negate" class="blue" value="+/- " onClick="NegateButton(); return false;"></td>
<td><input type="button" name="dot" class="blue" value="  .   " onClick="CheckNumber('.'); return false;"></td>
<td><input type="button" name="..." class="red" value=" +  " onClick="AddButton(1); return false;"></td>
<td><input type="button" name="equal" class="red" value="  =   " onClick="EqualButton(); return false;"></td>
</tr>
</table>
</td></tr>
</table>
</td></tr>
</table>
</td></tr>
</table>
</form>

<!-- BODY END HERE -->

Конвертер валют в евро:

Код:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">

<HTML><HEAD><TITLE>Euro Convertor by Mike McGrath</TITLE>
<META http-equiv=Content-Type content="text/html; charset=windows-1252">

<!-- TWO STEPS TO INSTALL EURO CONVERTER:

  1.  Copy the coding into the HEAD of your HTML document
  2.  Add the last code into the BODY of your HTML document  -->

<!-- STEP ONE: Paste this code into the HEAD of your HTML document  -->
<SCRIPT language=javascript>
<!-- Original:  Mike McGrath -  mike_mcgrath@lineone.net -->
<!-- Web Site:  http://website.lineone.net/~mike_mcgrath -->
<!-- BEGIN

var rate, index;

function locate(f,member,curr,r)
{
 f.country.value=member;
 f.currency.value=curr; 
 f.euro1.value=1;
 f.local2.value=1;
 rate=r;
 toLocal(f);
 toEuro(f);
}

function toLocal(f)
{
  if (f.euro1.value != "")
  {
    f.local1.value = eval(f.euro1.value * rate);
    if (f.euro1.value != 1)
    {
      f.local1.value=eval(Math.round(f.local1.value * 100)) / 100;
      f.local1.value=format(f.local1.value);
    }
  }
}

function toEuro(f)
{
  if (f.local2.value != "")
  {
    f.euro2.value = eval(f.local2.value / rate);
    if (f.local2.value != 1)
    {
      f.euro2.value=eval(Math.round(f.euro2.value * 100)) / 100;
      f.euro2.value=format(f.euro2.value);
    }
    else f.euro2.value=eval(Math.round(f.euro2.value * 1000000)) / 1000000;
  }
}

function format(str)
{
  index = str.indexOf(".");
  if (index < 0) str = str + ".00";
  else
  {
    str = str.substring(0, index + 3);
    if (str.length < (index + 3)) str += "0";
  }
  return str;
}

//-- END -->

</SCRIPT>
<!-- STEP TWO: Copy this code into the BODY of your HTML document  -->
<META content="MSHTML 5.50.4611.1300" name=GENERATOR></HEAD>
<BODY bgColor=black>
<CENTER>
<FORM name=euroform>
<TABLE cellSpacing=0 cellPadding=4 bgColor=gold border=0>
  <TBODY>
  <TR>
    <TH align=middle bgColor=blue colSpan=6><FONT color=white>Euro 
      Converter</FONT></TH>
  <TR>
    <TD align=middle><INPUT onclick="locate(this.form,'Austria','Schilling',13.7603);" type=button value=ATS> 
    </TD>
    <TD align=middle><INPUT onclick="locate(this.form,'Belgium','Franc',40.3399);" type=button value=BEF> 
    </TD>
    <TD align=middle><INPUT onclick="locate(this.form,'Germany','Mark',1.95583);" type=button value=DEM> 
    </TD>
    <TD align=middle><INPUT onclick="locate(this.form,'Spain','Peseta',166.386);" type=button value=ESP> 
    </TD>
    <TD align=middle><INPUT onclick="locate(this.form,'France','Franc',6.55957);" type=button value=FRF> 
    </TD>
    <TD align=middle><INPUT onclick="locate(this.form,'Ireland','Punt',0.787564);" type=button value="IEP "> 
    </TD></TR>
  <TR>
    <TD align=middle><INPUT onclick="locate(this.form,'Italy','Lira',1936.27);" type=button value=" ITL "> 
    </TD>
    <TD align=middle><INPUT onclick="locate(this.form,'Holland','Guilder',2.20371);" type=button value=NLG> 
    </TD>
    <TD align=middle><INPUT onclick="locate(this.form,'Luxembourg','Franc',40.3399);" type=button value=LUF> 
    </TD>
    <TD align=middle><INPUT onclick="locate(this.form,'Portugal','Escudo',200.482);" type=button value=PTE> 
    </TD>
    <TD align=middle><INPUT onclick="locate(this.form,'Finland','Mark',5.94573);" type=button value="FIM "> 
    </TD>
    <TD align=middle><INPUT type=reset value=Reset> </TD></TR>
  <TR>
    <TD align=middle colSpan=3>Country: <INPUT size=10 name=country> </TD>
    <TD align=middle colSpan=3>Currency: <INPUT size=8 name=currency> </TD></TR>
  <TR>
    <TD align=left colSpan=2><INPUT size=8 name=euro1> Euro </TD>
    <TD align=middle colSpan=2><INPUT onclick=toLocal(this.form); type=button value=equals> </TD>
    <TD align=left colSpan=2><INPUT size=8 name=local1> Local </TD></TR>
  <TR>
    <TD align=left colSpan=2><INPUT size=8 name=local2> Local </TD>
    <TD align=middle colSpan=2><INPUT onclick=toEuro(this.form); type=button value=equals> </TD>
    <TD align=left colSpan=2><INPUT size=8 name=euro2> Euro 
</TD></TR></TBODY></TABLE></FORM></CENTER></BODY></HTML>

Скрипт калькулятора почти как на Windows:

Код:
<html>
<head>
<title>WOweb.ru - Scripts - JavaScript - Windows Calculator</title>
<META http-equiv="Content-Type" content="text/html; charset=windows-1251">

<!-- HEAD START HERE -->


<style type="text/css">
<!--
body {font-family: helvetica}
p {font-size: 12pt}
.red {color: red}
.blue {color: blue}
-->
</style>

<SCRIPT LANGUAGE="JavaScript">
<!-- Original:  Steve Dulaney -->
<!-- Web Site:  http://www.hmhd.com/steve -->


<!-- Begin
var Memory = 0;
var Number1 = "";
var Number2 = "";
var NewNumber = "blank";
var opvalue = "";

function Display(displaynumber) {
document.calculator.answer.value = displaynumber;
}

function MemoryClear() {
Memory = 0;
document.calculator.mem.value = "";
}

function MemoryRecall(answer) {
if(NewNumber != "blank") {
Number2 += answer;
} else {
Number1 = answer;
}
NewNumber = "blank";
Display(answer);
}

function MemorySubtract(answer) {
Memory = Memory - eval(answer);
}

function MemoryAdd(answer) {
Memory = Memory + eval(answer);
document.calculator.mem.value = " M ";
NewNumber = "blank";
}

function ClearCalc() {
Number1 = "";
Number2 = "";
NewNumber = "blank";
Display("");
}

function Backspace(answer) {
answerlength = answer.length;
answer = answer.substring(0, answerlength - 1);
if (Number2 != "") {
Number2 = answer.toString();
Display(Number2);
} else {
Number1 = answer.toString();
Display(Number1);
   }
}

function CECalc() {
Number2 = "";
NewNumber = "yes";
Display("");
}

function CheckNumber(answer) {
if(answer == ".") {
Number = document.calculator.answer.value;
if(Number.indexOf(".") != -1) {
answer = "";
   }
}
if(NewNumber == "yes") {
Number2 += answer;
Display(Number2);
}
else {
if(NewNumber == "blank") {
Number1 = answer;
Number2 = "";
NewNumber = "no";
}
else {
Number1 += answer;
}
Display(Number1);
   }
}
function AddButton(x) {
if(x == 1) EqualButton();
if(Number2 != "") {
Number1 = parseFloat(Number1) + parseFloat(Number2);
}
NewNumber = "yes";
opvalue = '+';
Display(Number1);
}
function SubButton(x) {
if(x == 1) EqualButton();
if(Number2 != "") {
Number1 = parseFloat(Number1) - parseFloat(Number2);
}
NewNumber = "yes";
opvalue = '-';
Display(Number1);
}
function MultButton(x) {
if(x == 1) EqualButton();
if(Number2 != "") {
Number1 = parseFloat(Number1) * parseFloat(Number2);
}
NewNumber = "yes";
opvalue = '*';
Display(Number1);
}
function DivButton(x) {
if(x == 1) EqualButton();
if(Number2 != "") {
Number1 = parseFloat(Number1) / parseFloat(Number2);
}
NewNumber = "yes";
opvalue = '/';
Display(Number1);
}
function SqrtButton() {
Number1 = Math.sqrt(Number1);
NewNumber = "blank";
Display(Number1);
}
function PercentButton() {
if(NewNumber != "blank") {
Number2 *= .01;
NewNumber = "blank";
Display(Number2);
   }
}
function RecipButton() {
Number1 = 1/Number1;
NewNumber = "blank";
Display(Number1);
}
function NegateButton() {
Number1 = parseFloat(-Number1);
NewNumber = "no";
Display(Number1);
}
function EqualButton() {
if(opvalue == '+') AddButton(0);
if(opvalue == '-') SubButton(0);
if(opvalue == '*') MultButton(0);
if(opvalue == '/') DivButton(0);
Number2 = "";
opvalue = "";
}
//  End -->
</script>


<!-- HEAD END HERE -->




</head>
<body bgcolor="#EDEDED" text="#000000" link="#000000" topmargin="0" leftmargin="0">
<center>

<!-- BODY START HERE -->

<form name="calculator">
<table bgcolor="#aaaaaa" width=220>
<tr><td>
<table bgcolor="#cccccc" border=1>
<tr><td>
<table border=0 cellpadding=0>
<tr><td bgcolor="#000080"><b style="color:white">Calculator</b></td></tr>
<tr><td>
<table width="100%" border=0>
<tr><td colspan=6><input type="text" name="answer" size=30 maxlength=30 onChange="CheckNumber(this.value)"></td></tr>
<tr><td colspan=6>
<table border=0 cellpadding=0>
<tr><td>
<input type="text" name="mem" size=3 maxlength=3> <input type="button" name="backspace" class="red" value="Backspace" onClick="Backspace(document.calculator.answer.value); return false;"> <input type="button" name="CE" class="red" value=" CE " onClick="CECalc(); return false;"> <input type="reset" name="C" class="red" value="  C  " onClick="ClearCalc(); return false;">
</td></tr>
</table>
</td></tr>
<tr><td><input type="button" name="MC" class="red" value=" MC " onClick="MemoryClear(); return false;"></td>
<td><input type="button" name="calc7" class="blue" value="  7  " onClick="CheckNumber('7'); return false;"></td>
<td><input type="button" name="calc8" class="blue" value="  8  " onClick="CheckNumber('8'); return false;"></td>
<td><input type="button" name="calc9" class="blue" value="  9  " onClick="CheckNumber('9'); return false;"></td>
<td><input type="button" name="divide" class="red" value="  /  " onClick="DivButton(1); return false;"></td>
<td><input type="button" name="sqrt" class="blue" value="sqrt" onClick="SqrtButton(); return false;"></td></tr>
<tr><td><input type="button" name="MR" class="red" value=" MR " onClick="MemoryRecall(Memory); return false;"></td>
<td><input type="button" name="calc4" class="blue" value="  4  " onClick="CheckNumber('4'); return false;"></td>
<td><input type="button" name="calc5" class="blue" value="  5  " onClick="CheckNumber('5'); return false;"></td>
<td><input type="button" name="calc6" class="blue" value="  6  " onClick="CheckNumber('6'); return false;"></td>
<td><input type="button" name="multiply" class="red" value="  *  " onClick="MultButton(1); return false;"></td>
<td><input type="button" name="percent" class="blue" value=" %  " onClick="PercentButton(); return false;"></td></tr>
<tr><td><input type="button" name="MS" class="red" value=" MS " onClick="MemorySubtract(document.calculator.answer.value); return false;"></td>
<td><input type="button" name="calc1" class="blue" value="  1  " onClick="CheckNumber('1'); return false;"></td>
<td><input type="button" name="calc2" class="blue" value="  2  " onClick="CheckNumber('2'); return false;"></td>
<td><input type="button" name="calc3" class="blue" value="  3  " onClick="CheckNumber('3'); return false;"></td>
<td><input type="button" name="minus" class="red" value="  -  " onClick="SubButton(1); return false;"></td>
<td><input type="button" name="recip" class="blue" value="1/x " onClick="RecipButton(); return false;"></td></tr>
<tr><td><input type="button" name="Mplus" class="red" value=" M+  " onClick="MemoryAdd(document.calculator.answer.value); return false;"></td>
<td><input type="button" name="calc0" class="blue" value="  0  " onClick="CheckNumber('0'); return false;"></td>
<td><input type="button" name="negate" class="blue" value="+/- " onClick="NegateButton(); return false;"></td>
<td><input type="button" name="dot" class="blue" value="  .   " onClick="CheckNumber('.'); return false;"></td>
<td><input type="button" name="plus" class="red" value=" +  " onClick="AddButton(1); return false;"></td>
<td><input type="button" name="equal" class="red" value="  =   " onClick="EqualButton(); return false;"></td>
</tr>
</table>
</td></tr>
</table>
</td></tr>
</table>
</td></tr>
</table>
</form>

<!-- BODY END HERE -->



</body>
</html>

Вставлять куда вам больше захочется - либо в хтмл-верх, либо в хтмл-низ