1. Cut out silly or embarrassing pictures from a magazine and stick them on the passenger door of your targets car. They are sure to get some funny looks and honks from the public on their next journey. Obviously this will only work if the person approaches and gets into their car from the drivers side door.
2. For a great office prank, connect a wireless mouse to a co workers computer. You will be able to control their cursor from anywhere in the wireless mouse range which is usually about 30 feet (9 metres)! You can click on various things on their screen or just move their cursor randomly when they are trying to get their work done and they won't suspect a thing!
3. If you really want to play hardball with a roommate or friend who's bedroom which you can access, you can sew all of their long sleeve shirts sleeves shut. It has a similar effect to someone having their bed short sheeted but is a little bit crueler than classic prank.
4. The post it note special! If you have enough preparation time you can always cover your targets car or workspace in post it notes. You are actually able to purchase various colours of post it notes so why not use you post it note artistic skills and write a nice word on the side of their car or possible even draw a picture with them!