How to scare your friends with a special envelope

Scare people with the envelope practical joke in this video. This prank how-to video will show you how to really scare your friends or roommates using a nifty little device which you can build yourself. All you will need is a button, some thick copper wire, an envelope, some rubber cord, some pliers, and a roommate. After you've got your materials assembled, you can start unleashing havoc and scaring your roommates with this lovely envelope prank. Watch this instructional video, and learn.