This tutorial shows how you can enable Compiz Fusion on an Ubuntu 8.04 LTS (Hardy Heron) desktop (the system must have a 3D-capable graphics card - I am using an NVIDIA GeForce FX 5200 here). With Compiz Fusion you can use beautiful 3D effects like wobbly windows or a desktop cube on your desktop.

http://www.howtoforge.com/compiz-fusion-ubuntu-8.04-nvidia-geforce-fx-5200