My netbook dual boots Windows XP and Mac OSX 10.5, although after playing with OSX for a few weeks I can’t honestly say I enjoyed my experience so just use Windows XP 99% of the time.
I had to get a MacBook so that I could use Logic which my uni course uses.
After changing from Windows to Mac OS X I think it was one of the best decisions I ever made!
I have multiboot with Ubuntu 8.10 , Windows XP sp3, Windows Vista Home Premium and today I install beta version of Windows 7
Right now I download Linux distribution SuperUbuntu based on Ubuntu 8.10 and if I like it I remove Ubuntu 8.10 and put SuperUbuntu on my computer.