A very good scam, though. Gain some credibility and use that to get money until people realize what you're really made out of. At that point, you might have a product working and gain more trust. Run on that for a little more and keep going.
That box showed at Bitcoin Convention can be fake, very easy to do this.
Or they only have built like 5 of them. Back when Apple showed their first Apple ][ at the Westcoast Computer Faire in 1977 they only had 5 computers built. They did manage to deliver though eventually. Lots of computer companies in the '70s/'80s did the same and failed to deliver and went broke, leaving their customers holding the bag. The current ASIC market is VERY reminiscant of that early period of personal computing. Exciting times but potentially very costly if you make the wrong choice.