Ever seen: OK, it's not a real error message, but did anyone else see a programme called (I think) Alfred J. Glitch on the Apple ][? It fouled up anything you typed, and has some lovely messages. My favourite was "too tired to run error".
Ever written: plagiarised, but I couldn't remember where from even when I wrote it, and that was some years back. "Hit any key to continue or any other key to quit". The code shouldn't get to this point in the error trapping routines, but if it did, this should have got users screaming for help, which was what I wanted. I did document it fully, as though anyone would have read the documentation...