no, those computations are not useful for anything else. capturing the heat is really the best you can do.
Discussion
there's also the question of bandwidth. right now the miner only needs to send a single number over the wire, the nonce, and only when it actually finds a block. the rest of the results are ignored. if you instead wanted to transmit those, you'd be sending trillions of numbers per second, and that will add up fast.