Interesting concept, I was working with a company on a reasonably similar idea last year that was ultimately shelved in the end, but for a different target market.<p>You basically have to charge a reasonable amount for it, because it's not super straight forward. Sure you can buy a USB drive for $5 but it's not likely to be <i>that</i> great, you have to try and source drives that are reliable for a large number of R&W cycles and the really, really cheap ones generally aren't. Then you need to have a batch write process, so you can either spend time cobbling hardware together to do it or send it off to a company to do it, which costs a reasonable amount. Then marketing, then staff costs, then distribution costs. There's a lot involved in it, I'm surprised they're down so low, I'd assume they're running as nonprofit.