Universe Hopper was created by the Lax Viking team for Ludum Dare 39. The theme of LD39 was "running out of power".
You start grappled to a planet, orbiting it. When you click you release the grapple. You need to time it right so that you fly towards the next planet, and when you get close to the planet aim with the mouse and click again to fire out your grappling hook. If you're lucky it will latch onto the planet and you can move to the next one. As you fly you need to avoid the asteroids and other elements in space.
On the final planet is the one you're meant to be rescuing.
It's extremely difficult but has a compulsive "just one more try" element that keeps you going back for more.