TIP: eXpose on Gentoogentoo
Expose is a sweet feature to switch applications if you have opened thousands windows in your desktop. In the FOSS territory, here are two competitors: Skippy and expocity.
Both of them are in portage. Personally, I prefer skippy since it is has less
dependencies, only X and
imlib2. The only drawback is the lack of fancy
animation, and if you want to more advanced feature, like live snapshot, you
need to do some hacks to enable composition of your X11 server. Here is a
screenshot of skippy in action: