.GIF file sends me to a virus infested website?
 

I was searching pics of cute/funny animals, after downloading I hit the "launch" button and IE opened, my AV caught it thankfully. I'm confused as to how this could be done??

Thanks
Steel
(and I won't be launching from within lime wire again)

edit to add it wasn't a virus my AV caught it was a trojan, a few actually

anyone? anyone? How does someone hide a url in a .gif file?