The best quick set-up solution is the Easy Loop. The power in the Easy Loop is that the more weight that pulls on it, the tighter it becomes. It is quite fast and easy to undo.

Easy Loop in Action.

    The rope comes through the end-loop of the hammock (from behind), back around the "neck" of the loop. The rope then passes under itself without going through the hammock loop again. Now just pull the hammock ropes to make it tight.