Wow, I just realized how big stupid assholes you all are. That probably just puts me at you guy's level, so don't try to point it out.
Anyway, in all seriousness, I do know for a fact that on XP it changes your desktop background, puts tons of icons to flash on your desktop, locks you out of several important things like system restore, control panel, etc. and it has a keylogger. I think the keylogger has since been rendered harmless, but whatever. Some have said that it also fucks with your registry, but I dunno.
On Vista, it can do any amount of any of the above. Since it's a different OS, the effects can change around since the virus was coded for XP. To me, it just gave me a message saying how I've been infected with the stupid shit, and that's it. Others have had the desktop thing change, but I think all vista users have had access to system restore, so it was all easily fixed.