My fuck'n school

Our school likes to place things into our folders... I once found a wallpaper of snoop dogg on it. But, because I don't like the school, I gave myself administrator rights in the Mac lab (it's a student run lab), and then I'm just messing with all the iMac's, trying to overclock them, or another cool thing i can do is: Make them whisper whatever I want randomly... so you will be working, and all of a suddon it will whisper "I'm going to kill you" or something, rofl it's great. If you guys want to know how to do it, I'll tell ya!