Thought I'd share this for Mac users. I use this to run little windows programs (and games) that are only available for Windows. It's based on Wine, which is a Linux windows emulator, essentially. If you're interested in that, check out this link: http://www.winehq.org/
There's a list on there of programs that run in the current version of Wine (on which Winebottler is based) and how many problems you can expect. That list is right here: http://appdb.winehq.org/ There's no guarantee that all Windows software will load, but this does open a few doors. It's also [b]Intel Macs only[/b].
I know this came in handy for me, and I'm sure it will for some of you.