15. Hotkey Hell
With the help of a handy little program called AutoHotKey, you can wreak all sorts of havoc on your office mates' mental health. The program -- which, by the way, is actually quite useful for legitimate purposes, too -- lets you assign custom-programmed macros to any key combinations you choose.
Install the AutoHotKey program on your own system and take a few minutes to learn its scripting configuration. (It's not terribly difficult -- I promise. There are detailed documentation files and even sample scripts you can use to get started.) Decide what action you want mapped to what hotkey, and build your script. Then, use the program's conversion tool to save the script as an EXE file. Throw it onto your pal's computer, double-click it, and you're good to go.
The Final Product:
AutoHotKey is one powerful program, so the possibilities here are practically endless. You could create a script that'll automatically replace a certain string of text with something else, regardless of what program the person is in. Or you could remap a common hotkey like CTRL-P to do anything you want, like open Outlook and send a mass e-mail praising your suave appearance.
Hey, a compliment's a compliment -- even if you have to write it yourself.