My lovely friends are on holiday and have foolishly left me in charge of their house. I am going up there every other day to deal with post and make sure all is well and DD is watering their garden.
I have bought 20 small plastic yellow ducks and hidden them in their house. Not their bedrooms, I haven't been upstairs, but in the office, kitchen, playroom, downstairs bathroom etc. They are in the fridge, dishwasher, cupboards, hidden amongst soft toys.
Completely harmless but still amusing.
I need ideas for the next time someone lets me have their house keys.