Materials: pen tube, rubber band, tape, skewers, caps
1. Take a pen tube, making it by taking a pen and splitting it apart.
2. Attach a rubber band to the end of the pen tube, taping it on.
3. Take a cap and insert it onto the end of the skewer.
4. Shoot the skewer out of the pen tube and watch it explode as it hits into a wall or something....
Note: You usually have to get the trajectory of the skewer just right to get it so it hits a wall and explodes.
Here is the video to this project since it won't publish here: http://www.youtube.com/watch?v=0VageZVeOc0