Assault 3.0 was a heavily modified Ack!MUD, developed by Amnon Kruvi. Assault combined classic rogue-like, modern RTS and MUD to create a futuristic science fiction game where you could build, use technically sophisticated vehicles and deploy robotic cannons. Weapons found in the game ranged from auto-cannons to laser guns and most of the interaction took place on a 2D map drawn in ANSI color with ASCII characters.
After the game shut down, the developer released the source code to one of the players, who then made it available online (with permission) here.
A version of Assault-3.0 runs on port 4554 of orcs.biz (telnet orcs.biz 4554)