Aleph One is an Open Source 3D first-person shooter game, based on the game
Marathon 2 by Bungie Software. It is set in a Sci-Fi universe dominated by
deviant computer AIs and features a well thought-out plot. Aleph One
supports, but doesn't require, OpenGL for rendering.
Aleph One requires additional data -- shape, sound, and map
information -- in order to run. The easiest way to get this is to go
to http://source.bungie.org/get/, and download one of the scenario zip
files there. Unzip it, and pass the resulting directory as an argument
to alephone. For example:
alephone "~/Marathon Infinity"