The plasma saber idea utilizes plasma (obviously), a state of matter where one or more electrons have been added to or stripped of an atom. Plasma is seen in many places today; perhaps the most common is the neon sign. (Actually, not all signs use neon -- by using and mixing different gases, one can produce almost any color.) The idea of the plasma saber is to produce a beam of plasma contained by a strong magnetic field; imagine a stretched-out neon sign without the glass containing it.

This idea has serious flaws, however. It is true that one can shape a magnetic field to some extent, but it is nearly impossible to create an even, cylindrical magnetic field that extends about 3 feet and stops. Furthermore, all one would have to do to beat a plasma saber-wielder is to throw a kitchen magnet at him and interfere with the magnetic field containing the plasma. This is not to say magnetic fields are the only thing that could contain it, however; some new technology may be introduced that will allow us to contain plasma more precisely and efficiently.

As you can see, there are definitely more plausible lightsaber theories out there. I still consider it an option, though -- we don't know everything yet. As a matter of fact, I happen to have my own plasma saber -- although it does have a glass tubing for the blade. But it does fit inside a hilt, it does glow (it's blue), and it is plasma! It seems all that is missing is the containment for the plasma.

Go to the media section to see pictures of my plasma saber.