So, who's playing
Defcon then? (Think Wargames, the film.)
The demo is free, and lets you play certain game modes, including multiplayer and lan, in a limited fashion. The download page only just recently came back up again, but there are torrents for the demo too, kicking around.
I just finished playing the tutorial (I bought two copies, but I've not played online yet) and I have to say - destroying the population of whole continents is one of the stranger gaming experiences I've ever had. The music certainly helps.
There are other game modes, including Office Mode, Diplomacy, Speed Defcon, Tournament Mode. I imagine we on the forums here could organise quite a scary tournament...