When you pay $1000 cash into your bank account, would it prove you have paid this much if they send an email with an electronic signature saying that you paid $1000 cash? Would that prove anything in court, if the bank goes rogue and denies your paid that much? Inspired from bitcoin, where you can give someone cash and they give you bitcoins and the fact of the transaction is recorded in the bitcoin file you both carry, with some sort of encryption, can something like this be done to protect against a rogue bank?
A paper receipt is too easy to forge, the payee can claim in court that you have just printed a receipt in your printer or cash machine.
