Caretaker wrote:

Interesting stuff. Bitcoin is based on p2p mining; The miners do some kind of hashcode search as a proof-of-work. wouldn't it be better if the bitcoin miners will actually do some humanity benefiting distributed computing tasks (cancer research, SETI...)?

This is regularly proposed whenever anyone learns about Bitcoins. Mining, however, is hard from being useless. What the miner actually does, is encoding new transactions into a new block, authenticating them in the process. That's why they are rewarded with both mined coins and transaction fees. I don't think computations needed be SETI or Folding@home would be suitable. Unfortunately, mining created its own problem: a ridiculous arms race where more and more energy gets wasted on counting more and more difficukt hashes. Difficulty adjusts itself to the network's processing power and if you have better equipment then everyone else, your chance to find some Bitcoins grows. In the early days of this cryptocurrency, dedicating a CPU for hashing was more than enough. Right now, it's pointless to even start without a dedicated mining rig with several GPUs, and some miners are already ordering dedicated chips which are supposed to be even more effective. The end result is that more and more resources is wasted to do the same work. Generally, I don't see cryptocurrencies becoming useful before this problem (and the issues of scaling the protocol) is tackled. These features are pretty neat, though and will certainly contribute to Bitcoin's popularity if implemented.