exposé
Can I tell you, when Panther (MacOSX 10.3) was released, I moseyed on over to the Apple Store at the Glendale Galleria and played around with Exposé For those who haven't heard, Exposé is Apple's innovative desktop management solution. With a touch of a button, all your windows get scaled down and artfully tiled so that you can see all your apps. It may not sound like much, but, seriously, go to your nearby Apple Store or other Apple retail vendor, and play with the new OSX. (Alternatively, just check out the Quicktime demo of Exposéon apple.com.) The first time I hit F9, I think I almost orgasmed (yeah, yeah, I know, too much information.) It's soo cool.
Then there's this awesome hidden setting mentioned on macosxhints that changes the "show desktop" action so that all your opened apps to scale into a small box. Unfortunately, it's seriously buggy, and thereby not very usable, but hopefully Apple will eventually fix it.