Surprised that so many workplaces still use XP.
My three:
*XP "legacy" desktop I keep around for some old games and things that need SCSI, ZIP discs, and floppies.
*XP / Win7 dual-boot 2010 laptop, does everything from native dial-up modem and TV Tuner to USB 3.0, HDMI, ESATA, SPDIF, a card reader, and a real docking station.
*XP audio computer, my favorite. 2007 Dell, downgraded from Vista, has been online once for two necessary Windows updates. Otherwise it's an internet virgin with nothing but audio software and boots in about 8 seconds. Awesome.