Hi,
Now that beryl and compiz have kissed and made up, the new improved kid on the block is called "Compiz Fusion"
A nice how to for ubuntu-users - http://vorian.org/?p=82
Basically you need the packages from Trevino's repositories.
If you face problem with video playback windows then using ccsm (compizconfig settings manager ) add this to "General Options" > "Opacity Settings" > "Opacity windows" >
((type= Unknown | Menu | PopupMenu | DropdownMenu | Tooltip | Notification | Combo | Dnd | name=sun-awt-X11-XWindowPeer) | (type=Normal & override_redirect=1)) & !(name=sun-awt-X11-XFramePeer | name=sun-awt-X11-XDialogPeer | name=MPlayer )
Oh and keep watching for the new zoom out plugin. It works flawlessly on my measly T42 with 512 MB ram and ATI Mobility.
regards, C