Imagine Earth is a small indie game about building colonies on planets, while balancing out things like food, energy, renewable and non-renewable resources, emissions, temperate and happiness etc. Effectively it's a placement game - you can plonk down buildings, and they get increased or decreased output based on what's next to them. I think it had a pretty successful trip through EA and has come out totally playable, and in a much better state than it started in. The game starts out pretty slowly, but gets a little more complex the more you play. It can take a little while to get the hang of, but the dev has clearly spent a lot of time and effort making the UI and controls top notch.
