Two Japanese sewage workers have been working the same stretch of sewer for twenty years, one on the day shift, one on the night shift. Every daily change of shift as one is entering the sewer, the other is leaving. In twenty years they never say a word to each other. Anyway, they are both up for retirement, and as they are long serving, hardworking city employees, the city lay on a party for them. So there they are sitting there, both holding a drink, one of them decides he's going to break the ice. He walks over, says 'hello' - the other says 'hello' back, and says 'you know what, we've been working in the same place for so long, and never said a word'. To which the other replies 'I know, we've just been two nips that pass in the shite'.