Frontier is a modification of a game called Garrys Mod, Which is a modification of the Source Engine, where you utilize all the models from Half Life 2, CSS, TF2 etc and put them together in a sandbox environment. Frontier sort of takes this further by having a space themed building environment. I do this with 2 other people, a modeller and a scripter. I do the 3D environments you'll see in the video. This is a sort of heavy WIP thing I have going on so far. It's a scaled model of the solarsystem. (With a nifty moon base)