The nice thing about this, from what I understand, is that unlike Gumroad, it lets you sell things for < 99 cents. Obviously, that's a huge potential market.

I would guess the $10 minimum is a way to "hide" or "bundle" these tiny transactions that you can't efficiently handle through the existing credit card/banking system.

More generally, I guess the whole Minno business model/insight is to aggregate these kinds of small transactions that can't efficiently be handled by the existing financial system. (Minno is the payment service underlying Hawt Cakes.) This is literally speculation; I imagine the founders will correct me if I'm wrong.