Windows Vista / Windows XP / Windows NT / Windows 2000 / Windows ME / Windows 98 SE / Windows 98 / Windows 95
Openarena is a free open source version of Quake 3 Arena. It basically allows everyone (even on Mac and Linux) to play Quake 3, and for the community to continue to update and add content to the game. Openarena adds a ton of weapons, gametypes, skins, maps, and more. If you like Quake 3 arena but want more stuff, this is really the ticket. If you don't know what Quake 3 is, it's a mostly multiplayer first person shooter. It's one of the original deathmatch games with a lot of skill and quick reflexes required for truly mastering the game. Over the years the community has really added to the game and now you could play for days without repeating a map. The graphics are pretty long in the tooth but the game is free so there's really no reason not to try it if it sounds like your thing.