AJAX / PHP / CSS / Rollover code needed for simple project

I need code and example usage for the a roll over effect: example: **[login to view URL] ** When the user rolls over a link / image the following happens: 1. The popup opens and follows the mouse cursor [see example above] 2. the content of the popup [html] is retrieved via ajax and displayed 3. when the mouse leaves the item it disappears. a couple things: 1. it must work in in all major browsers [firefox, IE6 and IE7] 2. in browsers that don't support it, the link will open a standard popup when clicked. 3. I must be able to place multiple copies of this code on the same page without interfering with other items. if you need more information please ask. Thanks,