<i>&gt;The 21 Bitcoin Computer consumes 15W (5V @3A) and has an efficiency of approximately 0.16 Joules per Gigahash and arrives configured to calculate at a rate of approximately 50 Gigahashes per second.</i><p>So taking the computer&#x27;s price of $400 and using this calculator [1] w&#x2F; the current difficulty level, 50 Gigahashes&#x2F;s, 15W consumption, 5% pool commission, $0.15 $&#x2F;kW energy costs, and the current exchange rate of $332USD&#x2F;BTC we get:<p>$0.07 in daily revenue or<p>5714 days (15.6 years) to breakeven assuming constant difficulty and current exchange rate levels.<p>---<p><i>&gt; Please note: the satoshis you mine provide a source of readily-available bitcoin for application development, but are not intended to be used for investment purposes.</i><p>I wonder if they included this disclaimer because the 21 Bitcoin computer will never generate a profit, or because of some other legal barrier? Either way, they should stick &quot;NOT AN EFFICIENT MINING DEVICE, SOLELY FOR DEVELOPMENT PURPOSES&quot; at the top of their description instead of dancing around the issue, making it seem like they&#x27;re hoping to lure naive miners into purchasing the device.<p>[1] <a href="http:&#x2F;&#x2F;www.alcula.com&#x2F;calculators&#x2F;finance&#x2F;bitcoin-mining&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.alcula.com&#x2F;calculators&#x2F;finance&#x2F;bitcoin-mining&#x2F;</a>