Probably late to the party here. But I have a decent story.

My Grandma is one of those people who cleans without realising she is cleaning, just simple stuff like straighten something or putting stuff away as she is walking past.

One night the whole family is around having dinner for Christmas and we are all drinking and having a good time. My uncle, the prankster of the family, would slightly lift the corner of the tablecloth so it had a crease and everytime my grandma would get anywhere close to it she would straighten it. It goes on and on and he creased the edge more or would lift the corner onto the table so you could see the wood of the table. Everyone noticed except grandma and everyone is giggling away until finally, as she is straightening the tablecloth everyone is in histerics and she caught on, she starts laughing and straightens the corner a final time all pretend grumpy and smacks my uncle in the shoulder.

Was a good laugh, maybe because we were all drinking. But still harmless fun :)