Other operating systems: There's the usual Windows, Mac OS X, and millions of different Linux versions, but there's also: SkyOS (written from scratch), and Syllable (also written from scratch). Syllable is a free 31mb download for the Live CD so can easily be checked out. More info and links here.

Amiga people might want to look at AROS - an x86 Amiga OS aimed at being Amiga compatible. I wonder what would have happened if after the Atari Falcon (Atari's last proper home computer release), Atari decided to write/port GEM/TOS (Atari OS) for/to the PC? (Perhaps it could have been slightly successful allowing Atari people to move over to a familiar place?)

Syllable seems quite quick, but the general user interface is like going back to using an Amiga (it's a bit ugly / basic looking - in fact the default theme is called 'Amiga' - you can choose from Beish, Next, Win98, Warp looking windows etc), the calculator's called 'Albert' so if you wanted to find the calculator you look in the Albert folder (rather than looking in a Calculator folder). Plus when you're in the Albert folder you don't even know it's a Calculator until you run it (the icon is simply the default Syllable 'program' icon). Whisper is a mail client - again you can't tell till you actually run the program as the program icon doesn't show you a mail icon or anything to give you a clue what the program does. The internet works though (ABrowse - at least it gives you a slight clue as to what it does). Well, I managed to crash the desktop by changing the window themes and the resolution / colour depth at the same time. (So now I need to reboot - I think I'll reboot to something else though :)

And in more OS related stuff, apparently Longhorn* (Windows XP + X number of years) is basically no more secure than Windows XP + SP2 - I was expecting something half way decent, but instead it's likely Microsoft are just going to force people to use it by dropping support of W2K and XP in the future. *link to PCWorld preview of Longhorn.