Battle for Wesnoth http://www.wesnoth.org/ Vulture's Eye http://www.darkarts.co.za/vulture OpenArena http://www.openarena.ws/smfnews.php FreeCiv http://freeciv.wikia.com/wiki/Main_Page Naev http://code.google.com/p/naev/ UfoAI http://ufoai.org/wiki/News AlephONE/Marathon http://marathon.sourceforge.net/ Hidden and Dangerous http://www.atomicgamer.com/files/31068/hidden-dangerous-deluxe-full-game Scummvm http://scummvm.org/ + Game packs (scroll down) http://scummvm.org/downloads/ OpenTTD http://www.openttd.org/en/ Warzone 2100 http://wz2100.net/ Ur Quan Masters http://sc2.sourceforge.net/ Unknown Horizons http://www.unknown-horizons.org/download/ FreeCol https://en.wikipedia.org/wiki/SourceForge.net BosWars http://www.boswars.org/ WideLands http://wl.widelands.org/