so Kerbal Space Program is launching v1.0 today after being in early access for the last four years. for those who aren't aware of the game, it is a simulator where you build aircraft/spacecraft from set parts and then put little green people in them and fly them (possibly even to other planets if you have the skill), it is also extremely mod friendly, and I personally get a lot of extra functionality from mods. not that the base game is in any way lacking, I just prefer some of the hard mode mods. here is a link to their youtube channel. KSP is available on Steam, as well as directly from their site.
https://www.youtube.com/user/KerbalSPOfficial
https://www.youtube.com/user/KerbalSPOfficial