Demo Updated (8/29/2007): In addition to the image lightbox demos, I added four more types: text content, web page, web page with video, and embedded video. Check it out.
Yahoo! User Interface Library (YUI) provides a very handy class for creating modal dialog box with background masking, which can be used to create lightbox. If you have no idea what a lightbox is, you can run this online demo to get a taste of what it looks like.
There are several advantages to use YUI to create lightbox. The most important one is you get cross-browser compatibility support out-of-box. The above demo has been tested in IE 6, Firefox 22.214.171.124, Netscape 8.1, Mazilla 1.7 and Opera 9.21, which was created without any hacking. Another hot feature is that one can easily create a drag & drop lightbox without any extra effort.