Jason wrote: That is really cool.  It's one of those things that doesn't work if you think about it too hard -- if the shield absorbs all energy, how does Cap bounce it off things?  If he chucks it at a wall, shouldn't it just drop to the ground, having absorbed all the kinetic energy of the impact with the wall?  But, as has been pointed out many times, if you're thinking about it that hard, you probably shouldn't be reading the comic in the first place.

I always chalked up the rebound versus absorbing nature of Cap's shield due to the fact the shield usually bounces off of it's EDGE. It's unlikely the vibranium compound would allow that were the shield to hit on the broad surface of it's face.