Tonnes of CP.
Told my colleague immediately as he was at the other end of the work bench, then told my manager. They called the cops who told us to leave it alone, then immediately made their way over to confiscate the PC and take a copy of the job booking slip.
Never heard another thing about it after that. We thought we might be called as witnesses or to give statements, but nothing. The cops took a few mins with the PC when they got there, asked us to log into it and then leave the room. We figured they had enough on it and the guy probably admitted it. Never saw the customer again either, and he was a fair bit of a regular.