Have you become a Jedi in your Star Wars delusional mind? If so, break out of the the asylum with a Jedi lightsaber. Oh, but you don't have a lightsaber yet, okay. Well, this video tutorial will show you how to make a very inexpensive LED light saber with the most basic parts you could find. Novastar will shares his Jedi wisdom on LED light sabers, so pay attention, or you could never get out of that loony bin.
The only thing not mentioned here is the blade, which is best to be a 1" diameter polycarbonate tube with diffusion film (to catch the light) and a tip with mirrored film (to help reflect back some light). The blade (along with the 1.25" blade / LED mount / holder) can be found at thecustomsabershop.com