Spotted in a toilet of a London office:
TOILET OUT OF ORDER. PLEASE USE FLOOR BELOW

In a Laundromat:
AUTOMATIC WASHING MACHINES: PLEASE REMOVE ALL YOUR CLOTHES WHEN THE LIGHT
GOES OUT

In a London department store:
BARGAIN BASEMENT UPSTAIRS

In an office:
WOULD THE PERSON WHO TOOK THE STEP LADDER YESTERDAY PLEASE BRING
IT BACK OR FURTHER STEPS WILL BE TAKEN

In an office:
AFTER TEA BREAK STAFF SHOULD EMPTY THE TEAPOT AND STAND UPSIDE
DOWN ON THE DRAINING BOARD

Outside a second-hand shop:
WE EXCHANGE ANYTHING - BICYCLES, WASHING MACHINES, ETC. WHY NOT
BRING YOUR WIFE ALONG AND GET A WONDERFUL BARGAIN?