yeh being on a trampoline all day gives u a hell of a workout. I believe that using the trampoline you can experiment with different things to get the best workout for you, when on it i try to spent around 45-1 hour a session starting with a relaxed bounce before going into a intense work out on it consisting of
skipping: this may sound easy but it kills your arms after a short time, you need a set of decent skipping ropes and yu simply hit a good bounce and swing your ropes round (you should get doubles per bounce)
High Bouncing:self explanitory
front flips:fairly easy
grappling with a partner
And to finish off your partner shouting commands to you whilst your bouncing on the tramp ie touch the ground, reach up high, left jab,right jab.
The best thng about a trampoline workout is that it is in no way boring or gruelling. Its fun (until you wake up the next morning) and can keep you in great shape.