For this prank, you need some large pieces of cardboard, sticky tape, an inward-opening door, some time, and some random confetti. Stick the cardboard to the door posts to make a large wall of cardboard leaving a small space at the top. Make sure when you open the door that it opens away from the cardboard, and not into it. Then fill the space between the cardboard and the door with confetti, beads, etc., by pouring all of it down the space you left at the top.

The next person who opens the door on the other end (make sure it is not you!) will have an avalanche of confetti come pouring down right on them!

NB: This is a very messy prank, so it will be very hard to clean up all the confetti and other stuff you used for this prank, also make sure it is easy enough to remove the cardboard from both inside and outside the room.

Make a large web of transparent sticky tape on the door posts. Be sure that if you open the door the door opens away from the tape, not into it. The tape will be very hard to see, unless you already know it is there. The lighting in the room also affects how visible it is.

The next person who walks through the door way will get stuck in all the tape!

This is a very old, very effective prank for people who have several bed sheets.

First take off someones bed spread, and the sheet. Take the bottom of the sheet and tuck it in at the head of the bed, place the pillows on top of this. Take the rest of the sheet and fold it upwards so that it goes over the pillows. You then need to put the remaining sheet(s) and bed spread over this, and fold the part of the first sheet which went over the pillows down to cover the top few inches of the bed spread. It should look just like a normal traditional-style bed...

Now, when your target gets into bed, their feet won't go to the end of the bed and they'll go balistic!!! :)