Not your ordinary appearing text box

[JCal23]

Hey everyone,

I was on Amazon.com and came across a cool feature that I saw. At the top of their homepage there is a tab that reads "See All 36 Product Categories." When you float the mouse pointer over it a box appears with the categories you are able to get to from this one box. I would LOVE to incorporate this feature on my site. How do I do it. It seem like a basic pop-up but the way it appears and dissapears is very cool. Any help in doing this would be great.
Thanks, Jason

[LeeU]

You can try this one. There are others in that directory.. You can also check this site. It's all CSS.

[toicontien]

You might be interested in using a JavaScript library for this task. Something like mootools or Scriptaculous.