I don’t use compiz on my work computer(HP 520 laptop), but I do use compiz on my own laptop which has a NVIDIA 8400GS video card, the main reason I don’t use it on the HP 520 is that: it’s really too slow to run compiz smoothly with the default settings of Xorg and intel driver, but I hear that the 3D performance has been greatly improved in kernel 2.6.29, so I spent some time to get compiz work well with the HP 520(Intel 945GM video card).