MP - Good point, but the OP was talking about remoting *into* a Mac from a Windows machine, not vice-versa. ^_^
If the company allows it, you could always use a web-based service like LogMeIn. I've used it to remote into both Win and Mac from Windows, it works just fine, and the basic version is free (basic = no sound (I think), no Flash, no direct file transfers between the two systems (that's why I have an FTP server dammit), just straight-up "take over the Desktop/comp", but it functions as if you were sitting there at their comp otherwise). The only thing you don't get to see (unless they've fixed it recently) are the UAC popups in Vista/7 -- If those show up, you just get a static (unchanging, not "snow") screen until the user clicks it away.
"That was interesting. But dropping a warship on me is cheating. Take it back!" - Id, Xenogears
"You have good eyes. Now let's stain those eyes with despair. It's time to dance." - Vega, SF5
"The most dangerous phrase in the language is, 'We've always done it this way.'" - Grace Hopper
"Your math is correct, but your physics is abominable" - Albert Einstein to Georges Lemaître (re: Big Bang Theory)