Since i saw this video and it blew my mind, and it seemed to get good responses, I figured it was too awesome for it not to get its own thread
StarForge - First Playable Release
Basically, this game is like minecraft mixed with halo, with surprisingly nice graphics, physics based movement, voxel environments that are completely destructable (or mineable).
On top of all that, you will be able to go into space without a single loading screen. Eventually you will be able to build up forts and survive against aliens with your friends, or fight competitively and build your own base and mine resources like an RTS, among other things.
But you can go into fucking space from the planet.
Download links