I haven't noticed a single open source game listed yet (but I haven't exhaustively searched either), so I thought I'd offer the one that's been dominating my time lately:
Sauerbraten is a fast-paced FPS with a number of game modes, maps, and a fun community of players. They typically put out a new release once every quarter, with the "Winter" release scheduled to arrive sometime this weekend. The best part for me is that I can hop online for a 15min game and I actually feel like I've played, whereas 15min spent on many commercial titles feels like not enough time spent to do anything meaningful.
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I haven't noticed a single open source game listed yet (but I haven't exhaustively searched either), so I thought I'd offer the one that's been dominating my time lately:
http://sauerbraten.org/
Sauerbraten is a fast-paced FPS with a number of game modes, maps, and a fun community of players. They typically put out a new release once every quarter, with the "Winter" release scheduled to arrive sometime this weekend. The best part for me is that I can hop online for a 15min game and I actually feel like I've played, whereas 15min spent on many commercial titles feels like not enough time spent to do anything meaningful.