Rather than have standalone functions rtrim, ltrim, and trim (as in http://www.bytemycode.com/snippets/snippet/397/) why not have them as methods of all string objects?

Center Pop-up

A simple back button in JavaScript.

function to validate mac address

Remove control character from a string

Find min and max of an array

This code is used in an Educational Portal product but can be tweaked to fit your need.

This code adds a small icon next to the title of a 'portlet' that resides on the page. By clicking the portlet title, the portlet usually maximizes within the constraint of the portal template - but the extra icon allows for the portlet to be opened in it's own window.

This simulates an MDI interface.
(REQUIRES PopItUp snippet)

libNog is a 9k library to provide somewhat easier browser-independence. It is not yet complete, and will be continuously revised. It grew from this snippet, and is still growing as I find things I use often.
Presently, libNog features:

A way to browser-independently get an XMLHttpRequest object.
A set of simple methods for GET, POST, HEAD, and to include other Scripts.
Simple methods for className control
A completely abstracted form of getElement*
Browser-independent methods for attaching and detaching event handlers
An event-normalization routine
A simple one-command 'Stop the Event' routine
And the big one: A simplified Class object by which classes can be built in JavaScript.

The above link will point you to the API documentation and history of libNog, as well as where to download the library.

This one may get me in trouble or kicked off MySpace altogether, but I thought it would be a fun bit of CSS magic to post.

As some of you may already know, MySpace does a REALLY good job of preventing images, script and some other tags from being used to customize your space. They have even gone to the extent of using tables without ID's to do the layout.

Pretty ingenious, allowing some customization, but still keeping those annoying ads for single women available to me and my youth groups kids, my family, etc..

Well no more - I want my friends to visit My Site, not just MySpace - so I have a clever method of getting them to go there, instead of posting comments on MySpace...

Check out my space to see this code in action!
www.myspace.com/casper619

Gets a regular expression that'll search for any regexp pattern specified in the parameters.