Today we put our first game, "Meditation 5" under a GPL. With this, all our games are "liberated"; the source codes are all available and put under GPL3; for "Acid Flight" and "Meditation 5" this also goes for the assets except of the fonts (that we don't own).
Our games: The Vaults of Minos is a roguelite precision platformer with very fluid controls and an refined level generation. Assets are non-free, but you might download the demo and place the binary you can build from the source there; the resulting game will have all features available.
http://thunderperfectwitchcraft.org/VaultsOfMinos/index.html
Acid Flight is a version of "Icy Towers" put on steroids. You might experience a texture glitch when starting it, in this case just restart the game (might require a few attempts).
http://thunderperfectwitchcraft.org/AcidFlight/
Meditation 5 is an minimal, abstract light gun game designed around taoist philosophy that should be played with a controller.
http://thunderperfectwitchcraft.org/Med5/index.html
Check them out!