XPilot is a 2D space shooter game for the X Windowing System. I began playing this highly addictive game back in 1993 or so, and even created a few maps with my college roommate, Sean Cier. The game consists of a client program run on the player's machine, and a server run on the hosting server, to which the players connect. The playing field can be customized through map editors, and we spent a long while creating what we feel are the most insane maps available: Lair of Chaos (download link below). The game can be mastered in about a year of leisurely play.
I took a 4 year break from the game, but have just rediscovered it and started a server on my machine stealthboy.com. Feel free to join in anytime. My alias is Han Solo and my ship is shaped as the Millenium Falcon.
There is a new release of XPilot called Xpilot Next Generation, or xpilot-ng. It is backward-compatible with the old servers, so my Lair of Chaos server is still playable with the new clients. The game is pretty much the same, there are just some new fancy graphics.