What is the best way to do this? Rent a jackhammer and generator/compressor? Is there some way to use a concrete saw and remove slices at a time? If you have to hire pros, how much does it cost? A few years ago I read (wired?) about some cool tool that shoots nails at super speed at rock to break it up. I would so love to rent one of those. Does anybody know if it ever really came to market? Relatedly, what is the price of aggregate (gravel)? Does it go by the ton, or by cubic yard? Sometimes the internet doesn't reveal good prices like I wish it would.