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I have been exploring mining hardware at http://mining.thegenesisblock.com today. No matter what hardware I look at, all of them are making no profit by Oct 2014.
How is this a good purchase? I assume the answer is that if you spend 5K on hardware and electricity and make 60K back in bitcoin in a years time, then you can consider it a good purchase (even though the hardware is now losing money).
Also, how is this model sustainable? Will new hardware be developed fast enough to continue mining past the middle of 2014? Am I reading too much into that prediction tool?