Good add ons for GNOME?

I want to make my desktop look cool, what are some good add ons for it. I already have screenlets, and a weird theme. I'm running Ubuntu 8.04 LTS.

Thanks in advance,
Lollercopter101

[Prometheum]

Conky is always fun.

[bornkiller]

Eye Candy for your Gnome
http://gnome-look.org/index.php?xcon...1116fcc1ae1694

You can always try compiz and beryl, if you have a good supporting graphics card. Then go on to get something like cairo or awn, to launch your apps.