Put your gamercard on your Vista desktop
Steve, who works over on the Windows Vista team, has posted details on how to get your Xbox Live gamercard on the Vista Sidebar. If you have the February CTP for Vista, then using mygamercard.net, you can place your gamercard (or your friends or foes) onto the Vista sidebar.
Edit: Yea, I know you put it on your Mac (as a gadget widget ) or XP (on your desktop) but this shows you how to do in the Vista sidebar.