Alright well its not hacking but what do you do to mess with teachers or when your board do you....mhmmmm cant think of the word, 
Anywayz I do the following:
So...what do you do?
Anywayz I do the following:
- Change the start button text
- Change all the windows caption to "Mr. Teacher Sucks!" or w/e
- Hide the taskbar
- Run a program that displays a random image and when closed it runs twice more, usally I'll run it on another student's computer
- And just kill random processes to see what happens
So...what do you do?