Great article. I enjoyed it thoroughly. As much as I like WinXP (as compared to every MS OS prior), I think every day more and more about switching to Linux.

Once a day was BeOS, an incredible OS in which nobody trusted enough. Now there is OpenBeOS which turns quite well. You may also find SkyOS, very similar.

If you really wanna try something different but Posix compatible, try QNX !

Kochise