http://en.opensuse.org/Beryl
you can run it with native drivers from nvidia, aiglx, or with xgl enabled.
Note that in the wiki how to i linked above it tells you to disable xgl from running when using nvidia native or aiglx.
I have tried many different ways, and i edited my xorg.conf file several different ways. I am not saying it is impossible for it to work on my system I am just saying from what I have read it is a pain to get it to run on ATi cards.
Now, I also installed beryl on my nc4200 HP laptop that has an intel 965 express video chipset. It worked for about an hour and then crashed X, so I just reverted everything back and it seemed to work like it did previously.
beryl is still in beta development so there is definitely going to be issues and it won't work out of the box on every system. However, once it becomes a stable package I can see beryl window manager being bundled in OS installers as an optional out of the box. This is partially due to the manufacturers of 3D cards not writing decent linux drivers. Once they have good kick ass native Linux drivers beryl should run with out a hitch on just about any system.