Xonotic - Xonotic is a free (GPL), fast-paced first-person shooter that works on Windows, OS X and Linux.
Houseparty - Brining empathy to online communication.
Counter-Strike - Counter-Strike is a PC-exclusive FPS video game developed by Valve Corporation.
Booyah - Video chat with up to 12 friends at the same time.
Quake - Quake is a series of first-person shooter video games released by id Software.
Slack - A messaging app for teams who see through the Earth!