If you like playing around with other operating systems and you haven't checked out the free vmware player, you definitely should. You can download a ton of different free appliances: NAS servers, linux distros, etc. Run them from your desktop without restarting or giving up your M$ habit.
Also, another piece of cool software: VirtuaWin which is allows you to have multiple desktops. Just like MacOS X's "Spaces". You can even run a full-screen VMWare player in a separate "desktop". Great for people who don't have multiple monitors.