Return On Investment
As of right now, my Antminer S1 has been hashing nonstop for 147 days. It has generated a shade under 1 BTC. That's good enough for ROI!! This marks an important milestone for my case study, as it proves that money can indeed be made from entry-level mining. Hopefully my ROI timeframe will provide a useful yardstick for other investors, who want to know roughly when they will start turning a profit.