I've been playing a ton of Space Engineers over the last week or so. It's a new game in development, and is currently available as early access. It's a voxel game that allows you to build your own star crafts and space stations (with more features coming out every two weeks or so).
It works similar to Minecraft. You can build things by connecting a series of differently shaped blocks/parts. Amongst which are also nuclear reactors (for power), gravity generators, thrusters and all other sorts of things you need for stations and star crafts. But what I really like is that it isn't as attached to the blocky aesthetic as Minecraft is, which results in a much more realistic looking game.
The little dude in the black space suit is the player character. As you can see, you can go nuts with size. Though, you do have take mass into consideration. The one I'm standing on is 15 million kilograms last time I checked. You need tons of power, thrusters and gyroscopes to fly it.
(Smaller ships have cockpit view.)