You've probably played Portal. (If you haven't played Portal, for the love of God go play Portal.) Assuming you have, use Portal as a starting point, but instead of a portal gun, you have a marble. And you throw that marble around the world, and it bounces off of things and makes lovely sort-of-physics-based parabolas as it careens off of walls and platforms. And whatever path the marble took, you can then fly along. Need to cross a lengthy gap? Bounce the marble down a long hall and then skip across like a stone over the water. Need to get around an impossible corner? Bounce the marble off a wall so that it makes a similar corner. That's Sphere. In their words, "a puzzler about trajectory transmission."
Here, the video will help.
It's free. It's really clever, and when you figure out a new puzzle you feel pretty brilliant. It runs on Windows or Mac. If you're patient it'll even play in your browser, via Unity. There's really no reason not to try it right now. Go!