Our latest copiers lock up when you try to copy currency... apparently . They actually do, we've had students try it, unfortunately for them we know who they are as the server records the last known user.
The second gen colour copiers were pretty good (they just did what you asked), just the paper let them down, although I got a forged £20 from an insurance refund on 120gsm ordinary paper (trust absolutely no one in Midsomer Norton!).