I "Gave Up" Windows a while ago, and now run Mac only. I still get regular calls from friends in need of help. Yesterday I replaced a hard drive in a friends Mothers machine, and re-installed Windows Vista.
What shocked me was the sheer amount of time it takes to perform a clean install.....Her retail copy was minus any service packs, and even with my fast BB connection, the process took me some 3-4 hours to complete.
I must admit, I am happier in my Mac world these day's, but it's good to keep your hand in.