Davidu
 
My very own forum. You can discuss pretty much everything
here. But do make it constructive...

dune2k
 
The best organized Dune community on the net.
Here you'll find everything from Dune topics to various
games and even international politics.

ValveErc
 
One of the largest Half-Life editing forums on the web. From the
website you can download both the Half-Life SDK and the
Valve Hammer^® that are essential if you want to create a
Half-Life MOD.