While watching the Leonid shower I had an idea for space mining. One of the main arguments against mining asteroids is that it would cost too much to bring the stuff back to Earth. My thought is why fly it back when you can just drop it. The asteroid could be cut into small chunks (5'x5', 10'x10', 20'x20', or what ever) by high power lasers like blocks from a quarry. Brought back to Earth orbit and simply dropped from orbit to re-enter the atmosphere in a deserted location. While some of the block would be lost due to friction, most of it would remain intact and make it to the ground and a recovery vehicle could pick it up for processing. I'm not sure if this approach has been thought of before, but it seems to be a simple idea.