It seems quite popular in China, so I always try to play a prank every year. Doesn't always work. Some that have - changing her laptop so that the screen is upside down (not sure why that is even possible, but on that laptop it was possible with ALT-cursor keys).
Changing all the clocks in the apartment and her watch to one hour ahead. And the clock in the car.
Filling her car completely full of balloons so she couldn't get in.
Recording the sound of the doorbell, and looping it in an MP3 player so it goes off every 5 minutes, hiding MP3 player and speaker near the door. I was actually away on a business trip, but still managed to pull this one off.
Two that didn't work - Clingfilm on the toilet. She didn't even mention it, she obviously wasn't amused.
Printing out a photo of my head, sticking it in a large glass specimen jar, filling with coloured water and placing it in the fridge. I got the idea off the internet, but it just didn't look realistic enough.
I completely forgot about it this year, guess I'm too late now.
