http://www.apple.com/macosx/features/expose/ if anyone hasn't seen the hype yet. F10 (tile all) and F11 (hide all) aren't that revolutionary, but F9 (scale down) is a fun trick.
I am surprised that that a work-alike hasn't been integrated into Gnome or KDE yet, but even without Googling I am sure something similar is being worked on.
I vaguely remember seeing one, it's called.. <damn, hang on, back in a Google> ...ah, that's right, Skippy.
http://thegraveyard.org/skippy.php
On seeing skippy-xd listed there, I can see how the use of xdamage, xcomposite etc could be very useful in this context.
I'll be downloading and trying that out myself :)
The page also mentions something called "expocity". Anyone tried this?
My Foontling Turlingdromes, Ten
...
Ah, but the choice of dreams to live, there's the rub.
For all dreams are not equal, some exit to nightmare most end with the dreamer
But at least one must be lived ... and died.