fisk0: Warzone 2100. Not a perfect RTS by any means, but it has a lot of very interesting ideas, rather unique gameplay - somewhat similar to Total Annihilation when it comes to resource management and focus on
long distance artillery capable of striking anywhere on the map, and customizable/modular units and a ridiculously huge tech tree that I actually think is more extensive than in any of the Civilization games.
Since the source code was liberated in 2004, and all the assets in 2008, it's still in active open source development, and had a new release just a week ago.
HereForTheBeer: Hmm, spent a LOT of time playing this game. The idea of the, uhh, commander units (can't remember if that's what Warzone calls them) is really cool, and it's also an interesting twist to have dedicated artillery spotters that gain experience from the arty they support. Oh, and a nice campaign game, too, with persistent units and experience. The tech tree is very deep, as you say, and provides several different means to whupping the enemies.
I'll agree with you and highly recommend this title for fans of RTS. It's not the prettiest game around but the gameplay is quite good, IMO.
Yeah, the campaign is rather unique, and the commander units are an interesting concept, basically working as a control group even though the game already has the traditional RTS control group setup - but the commander units can be a lot more automated - I love how they can take over factory production and use artillery support.
The only things I somewhat dislike in the game is the bad mouse and camera controls, something that is true for almost all the 3D RTSes, but especially the mouse issues are particulary noticeable in Warzone 2100 I think.
That the game really only has one faction is a bit boring too, even though the extensive tech tree means that there will be a bit of variation between players in a multiplayer game anyway.