Osmos

Osmos is a great example of innovative game design, and an excellent physics driven experience. The price is a bit higher than I'd expect at 9.99, but I don't know if that's to expensive

Long story short, you control a blob of goo in an essentially weightless environment. You propel the goo by poking holes in it's membrane, resulting expulsions shoot the goo in a given direction, sacrificing mass for speed.

Weightless goo as never experienced before.

It sounds simple, and it is, but it's actually quite engaging, you can't move too fast or you'll get absorbed by bigger blobs, can't move to slow or same result, and directions don't change unless you hit a wall or sacrifice more mass. It takes a real balancing act to handle and a not a little bit of frustration.

I'm giving this one 7/10, it's worth looking into and the price isn't too high, but I can see the game requiring large amounts of cool-down time between plays or frustration will burn you out.