My happy place is learning about cool things made by cool people with their own two cool hands. A self-powered, actually credit card-sized computer definitely fits that bill.
Now, some would describe any number of Raspberry Pi computers as 'credit card sized.' I'd personally love to see those folks attempt to slide one of those boards into a wallet—or even a jean pocket, for that matter. Reddit user krausler also takes umbrage with describing the Raspberry Pi this way, so they've only gone and made a teeny tiny computer that could neatly slide under my keyboard.
