Just thinking back to some ideas I saw or had during my childhood. The first thing that came to mind was a rubberband strung between the thumb and first finger, to shoot a half of a paper clip like a slingshot would work. Next was a drinking straw blowgun. The darts are made from a shoelace end and a straight pin (with a head). You cut the plastic end of the shoelace along with about the same length of braided lace. In other words twice the length of the plastic tip with some lace also. the half that doesn't have the plastic tube covering it gets frayed and the pin shoved through from the frayed end of the tip. They should look like this a little. http://cdn.instructables.com/FW8/X3JJ/3XPET2JYFRC/FW8X3JJ3XPET2JYFRC.MEDIUM.jpg Don't try to inhale one of these things please. I had an idea to make a pistol cartridge into an exploding dart. It worked well, but much too dangerous to describe what's involved with building one. I would not recommend making one. If someone did try it, they would want to throw it as far away as they can. you don't want it to land anywhere near people. Lastly I made knitting needle lawn darts using duct tape made into flight feathers.