(1) Go in someones Underwear drawer and Safety Pin all their underwear together
(2) Set all the clocks forward an hour (or two)
(3) Put a piece of tape or a piece of a sticky note on the mouse of the TV remote.
(4) Freeze a bowl of cereal overnight and then in the morning put a fresh layer of milk on top and give it to someone.
(5) Take a diaper and put melted chocolate and put it on the table. (ha ha ha!)