XP Pro on both computers at home. I'm the only one with XP Pro at work; most of the others are Win98se, with a couple of W2K's thrown in.
Up until about 8 months ago, I also had a 386 running a custom Linux kernel at home for a firewall. Finally got rid of it and got one of the little cable routers. A lot quieter and doesn't take up near as much space.