not. attraction is independent of magnets(which have cubic magnetic falloff). magnets only work on some metals(Iron, nickel, cobalt, gadolinium, dysprosium(not sure if this is the right spell), while attraction works on all of them.
if you want to know how attraction calculations are made(assuming they have an attraction of 0.5, as phun calculates using the attraction sum as a post-calculation multiplier factor), click here.
the invisible drive shaft links are done with the circles - thay have been glued together... and for the cylinder, he put the script on the drive shaft links-.-
anyways, nice engine, 10/10
also, the moon bombing is actually kinetic - a 2 ton missile - earth has twice the moon's mass and suffered a 50 kiloton explosion, but it's orbit hasn't been altered. AND there's no orbiting camera to check it....
AND completely off-scale.
you can use as another formula for calculating the angle, which is less CPU-Intensive = 2*Math.atan(e.normal(1)/(e.normal(0)+1), because e.normal's length is always 1.
also, it's able to lift itself...
it's got rotational damping - due to dircle spawning. reduce spawned circle's density, while increasing ALOT it's velocity to compensate for it(1e-10 density for spawner should be ok)
also, it's better to have an specialized refresher for the scene - 2 refreshers create huge lag.