At work I have a Dell Optiplex GX270 with an integrated Intel Extreme Graphics 2 chip. I installed Ubuntu and Beryl, but Beryl was giving me some trouble. Things were slow and the gradients were bad. I thought there was some graphical limitation that didn’t allow me to use certain window decorations, because pixmap-based stuff worked fine. I went back to Metacity and forgot about it for a while. Later I decided to rotate my display for text reading and tried Beryl again. After some troubleshooting I determined I needed a new driver (sudo apt-get install xserver-xorg-video-intel). It broke rotation, but at the same time I discovered I’d been running in 16 bit color depth! I changed it to 24 bit and with the new driver Beryl looks amazing and runs smooth.
Note the choppy gradient in this before picture (how silly could I be?):

Now after the new driver and correct settings (also note the spiffy icons):

Much better. Wow, I hope I get inspired to post more interesting stuff soon.