Just got KDE4 working with my Gentoo installation, and this is the first post I've written to TGC using it.
Since I have two GTX 580s, I figured I have enough power to use compiz fusion without any slowdown. This is the case, but something's not right with the window decorations and the compiz desktop cube conflicts with the KDE desktop cube, so there's some weird behaviour when using both.
I do have wobbly windows and some effects enabled (such as windows bursting into flames when you close them).
Here's a demo some of the features, for those who've never heard of compiz fusion:
It really is the ultimate eye candy.
UNIX is simple and coherent, but it takes a true genius to understand and appreciate its simplicity -- Dennis Ritchie