JavaScript Code

Make an image change when the mouse moves over it
Make a page/image open a new window
How to tell what browser is being used
Show text in the status bar
Disable right-clicking on a web page
Change images using a dissolve effect
JavaScript doesn't only do useful things, you can play moronic games as well - Meme, Battleships, and Same.

JavaScript resources

Joust - Windows Explorer type navigation for your website using JavaScript - freeware download
Play JavaScript Chess against you computer, or learn how to play through old games using JavaScript.

Some JavaScript help from Microsoft :-

Make links underlined/change colour when the mouse hovers over it

First, define the attributes in the STYLE tag within the HEAD ie
<style type="text/css">
Then define the JavaScript functions, again within the HEAD, to actually change the attributes ie
<script language="JavaScript">
function do_over(myElement) {
myElement.className = "over";

function do_out(myElement) {
myElement.className = "out";
Finally, within the HTML, define the links as
<a href="" id="link1" class="out"
onMouseOver="self.status='Link to Queensryche's (Seattles finest band) official web site'; do_over(link1); return true"
onMouseOut="self.status=''; do_out(link1);">
Queensryche - tell me more</a>