I thought I would post this in case someone else was looking for it. Because I searched for quite a while and never found it.

I was using Thickbox to display some inline hidden content on a page. I wanted to activate Thickbox when a link is rolled over. To do this you must just add this code to your link:

onmouseover="tb_show('', '#TB_inline?height=530&width=
546&inlineId=hiddenModalContent&modal=true', null);"

So a complete link might look like this:

<a id="skip" href="#" class="thickbox" onmouseover=
"tb_show'', '#TB_inline?height=530&width=546&inlineId=
hiddenModalContent&modal=true', null);"></a>

I had to break the code in certain places to make it fit correctly on this page. So just make sure there are no spaces or breaks in your version.