If you have access in another guy's computer and can use the browser, you can make his computer almost unuseable. For Netscape Navigator, go to Options, Preferences, and change the start page to "/con/con" (without quotes). For IE, got to TOOLS, INTeRNET OPTIONS, and set the home page to "/con/con" (without quotes). Everytime the browser starts, the Blue Screen of Death comes up and the internet will not work at all, unless the computer is restarted.
The easy fix would be to go into explorer Tools - Internet Options -Change the homepage. But there is seems to be a problem in that...aha! Once you go into explorer, you crash! So, the right thing to do is to right click on the Explorer icon on the desktop, go properties, and change it from there! I think it's around the same for Netscape. (Note: typing /con/con in the toolbar and pressing also yields the BSOD, for those of us who want to commit PC suicide.)