Arduino prank ideas - please post your ideas!

I had a freind that got gloriously drunk at a work christmas party. Someone had decided to hand out disposable cameras at the same party.

Cut a long story short i wrote a windows service that set a different picture of him getting plastered as his wallpaper everyday, I hid the pictures inside the executable and gave it a credible name. If that machine is still running, I sure the slide show is still going to this day.

Duane B