Hello I didn't find anything interesting in Singapore but I saw this signboard from the web http://sggeratberlin.blogspot.com/2009/06/very-impact-and-yet-funny-sign-board.html

I think it's funny because of the ambiguity in the sentence.

'Drop your pants here and you will receive prompt attention' can mean that the customer can bring his dirty pants and the shop assistants will attend to him quickly to help him wash his pants.

'Drop your pants here and you will receive prompt attention' can also mean that the customer will receive a lot of stares if he suddenly removes the pants he is wearing =)

- Cheryl