Out of all the item tooltips I have seen, the JS here is the best by far that I've seen. Currently, I am working on a script in my spare time that will probably the freely released sometime in the future and was wondering if I could implement your JS for some of my own tooltips, of course noting the source of the code.
http://area52.14716.info/armory.php?c=2 is an example of a page generated by the script. The current tooltip implementation is wz_tooltip, which while isn't horrible, doesn't seem to be really made with this type of stuff in mind and is somewhat lacking. It is LGPL'd code though, so I feel comfortable including it.
I don't want to step on any toes and piss someone off by using code without asking. Thanks.