A chap got a job working at a precision engineers. His starting post was going to peoples' houses collecting bubbles from goldfish bowls to put into spirit levels.
First job I was on, there was a bucket of Swafega. I said, 'Urgh, what's that stuff for?' They said, 'You put your hands in it to clean them'. 'Aye, I bet, you must think I'm stupid or something'. They were right, I was.