Let me say, I do not think they are scrap. They do have a value, it is just pretty low. They can be used as an FPGA dev platform. That is why I say I would buy a few for $30 each. But I will never get that $30 back mining BTC.
Last I checked they were cryptographically locked to BFL's FPGA images and BFL won't provide the info needed to reprogram them. IIRC they also can't be reprogramed over the USB bus.