Now, at first glance, you may think this is a javascript search engine for your site. NO! This can only search for certain text strings within the page you are at. However, it is still a very helpfull script. This is great if you have a really long tutorial site or something similiar that is several pages long and want to give your users the ability to find what they want from the text really fast instead of having to look down 5+ pages of material.
The source...

<script language="Javascript">
<!--
// original content taken from Nic's JavaScript Page with permission
// lack of these three lines will result in copyright infringment
// made by: Nic's JavaScript Page - http://www.javascript-page.com

var numtimes = 0;

function findinpage(str) {

if (str == "") return false;

if (document.layers) {
  if (!window.find(str)) {
    while(window.find(str, false, true))    n++;
  }
else numtimes++;

if (numtimes == 0) alert("The word \""+ str +"\" was not found on this page.");
}

if (document.all) {
var txt = window.document.body.createTextRange();
var found = txt.findText(str);

for (var i = 0; i <= numtimes && found != false; i++) {
  txt.moveStart("character", 1);
  txt.moveEnd("textedit");
}

if (found) {
  txt.moveStart("character", -1);
  txt.findText(str);
  txt.select();
  txt.scrollIntoView();
  numtimes++;
}

else {
  if (numtimes > 0) {
    numtimes = 0;
    findinpage(str);
  }

else alert("The word \""+ str +"\" was not found on this page.");
}
return false;
}
}

//-->
</script>
<form name="search">
<font size=3><input name="string" type="text" size=15 onChange="numtimes = 0;"></font>
<input type="button" value="Find" onclick="return findInPage(document.search.string.value);">
</form>

Nic's JavaScript Page