I want to animate a ball rolling and falling off the table, and i wanna use a motion path... BUT: when the ball is falling off the table, i want it to move faster than when it's rolling. I saw this "set motion path key" but i don't know what that's for...

I want to just snap the ball to the curve, and then move it with the move tool, and set keys, kind of what you can do in flash, except here, when you move the ball it comes off the curve: I want it to stay "Snapped" while i'm moving it.

Thanx