This is a article that I have thought of myself based on the plasma saber article. This relies on the article of a "force field" -- something that doesn't exist yet. I'm researching it though, and I'll edit this if I find anything interesting (and plausible).

The reason I did this is because of the major flaws in the original plasma saber design -- from what I could think of, 1) The plasma would quickly dissipate into the air; and 2) The plasma, even if contained by the magnetic field, would not stay in place if exposed to another magnetic field. Thus, I believe some other field is required. This other field must:

If one could generate such a field and somehow mold it into the right shape, I believe they could make a lightsaber with it. My design is as follows:

There would be a pressurized container of gas of some sort (the same kind they have in neon signs -- not necessarily neon though). This would have a nozzle of some sort that is reinforced so the container doesn't burst when the gas is released, as it would have to be a fairly high pressure in order to fit the amount of gas required in a small space. Also in the hilt would be the force field generator and a gas ionizer (basically two electrodes) and a HV power supply. I have the last two components in my own plasma saber. When one presses a button to ignite it, the force field would begin taking shape. It would be produced so as to have a vaccuum on the inside. Then the gas would be released into the vaccuum and become ionized through the electrodes and HV power supply. This would essentially be the same thing as my plasma saber, except with a force field instead of glass/acrylic tubing.

It is important to note that there must be vaccuum on the inside of the force field, and that the force field not let air in or plasma out. Otherwise, it operates on the exact same principles as my plasma saber, or just a regular neon sign. In case you're wondering, though, my plasma saber does NOT have an electrode on each end of the tubing as neon signs do. I'm not sure exactly how it works, but it does.

The only problem with this article, obviously, is that force fields as I have described do not exist. I believe a magnetic field would not work -- no matter how strong -- because the gas would quickly become de-ionized (is that even a word?). Obviously you need to keep supplying it energy, but it seems to me that it would dissipate into the air rather than simply be suspended, magnetic field or not. After all, plasma "wants" to return back to its normal gaseous state, and it seems to me that one could not force energy into it when it is simply being suspended in the air. However, I'm no expert, so research it yourself and find out.