Ubuntu and Windows 7 in double boot. Both at home and at work.
Mostly use Ubuntu, and only boot with Windows 7 for Adobe Illustrator, or some games basically.
I'm sure Ubuntu will become widely used if they keep improving it the way they did the last few years!
Lot's of fun to come!
Latest Ubuntu LTS is really awesome! It has made so much progress since it's beginnings! Even in things as driver support! Now it's easier to install hardware on Ubuntu than on Windows! I had a 3g dongle to connect at a few computers in our office, and windows needed the driver cd otherwise it...