WARNING: EXTREMELY GEEKY CONTENT!
You might want to get your girlfriend away from the computer for this one.
Okay, let's talk about lightsabers.
So now episode III is out, and a whole wave of people will be interested in lightsabers again. I have been fascinated by the lightsaber since I was in 6th grade and first saw "Empire Strikes Back." I used to draw plans for a real lightsaber and used to postulate on what might make it work in real life. Looking around on the internet in the past couple of years I have found so many awesome sites about making replicas of the movie's prop lightsabers, custom lightsabers, lightsabers with electro-luminescent blades, ones with flourescent tube blades (bright but fragile), etc. There are many fabulous ways to have a semi-realistic lightsaber. I want the real thing though. And here I will discuss ways that it might be possible. I know its sci-fi, but imagination is an amazing thing from which creation can be born. If you are cynical about this, you can go be cynical somewhere else and pout and pout and pout.
There are a couple of pages on the net talking about the current technologies which hold potential, but they weren't thorough enough for me, so I've done my own research.
First of all, anything laser related is out. Light wont stop 36 inches away from your lightsaber hilt. The bright light we see from the blades in the movies should be coming from the energy of the blade itself.
I'll tell you what the best bet is: plasma. Imagine a column of plasma, which is what you see inside neon lights and flourescent lights, but instead of a glass tube, some other force containing it. And that force would have to be magnetic; plasma is a gas which is extremely excited and ionized, which means it adheres to magnetic fields. So theoretically, so far, we have a column of plasma coming out of a grip wich also generates an electromagnetic field to contain it. This would be perfect: plasma is extremely hot, so it would cut the shit out of anything it came in contact with, but being that it is contained within a magnetic field, the only thing that would repel it is another magnetic field (the magentic plasma blade of another lightsaber). Now, there are a few problems. One, is that plasma is so hot that it would melt the hilt and your hands once it was released. Secondly, the power source as of yet could not be as small as a footlong handle. Third, the magnetic field may be disrupted by other magnets in such a way that the plasma would leak out and really cause a serious problem. There is a very interesting part of plasma physics and fusion research called Inertial Electrostatic Confinement - containing a plasma in an electrostatic field which accelerates charged particles radially inwards, usually in a spherical but sometimes cylindrical geometry. We would want the cylindrical one. But this technology would not yet be able to be contained in the handheld unit we'd need. Damn. It is close though, and the right idea. Keep in mind that the first computers filled an entire room, now they can fit in your palm and do things the big old ones never dreamed of. A lightsaber wouldnt be the most practical weapon for war, but it would certainly be marketable enough to be worth the trouble of creating it. It might even bring some class and respect back to the world.
So ultimately what we need is improved energy cell technology to power this amazing contraption, the right kind of plasma source, and the proper electromagnetic or electrostatic field generator that would safely contain the plasma without being magnetically disrupted by magnetic objects.
Some lightsaber links:
Parks Sabers - These beautiful custom-made lightsabers are probably the best way to go if you want a top-of-the-line lightsaber toy. I certainly want one. I've heard the blades are nearly indestructable and the hilts are high quality. Notice the Arc-Wave is similar to Luke's in episode VI, the Avenger like Obi-Wan's in episodes III & IV, and the Rogue like Anakin's in episode II.
Lightech Industries - Another maker of EL lightsabers and accessories. Now I personally dont like their hilts, but I have heard that their blades are the brightest. It is here were you can buy a 'blade kit' to make your own. They also have a motion-sensitive sound module wich you can install in your lightsaber.
The Parts of Star Wars - Here is an amazing online resource for information and photo references of props from Star Wars movies and how they were put together, even where to find the parts to make them. The Prequel lightsabers are lacking, only through the Phantom Menace, but those lightsabers were all mostly machined from solid aluminum anyway.
The truth about Plasma Lightsabers - An article about the potential for plasma to create a real-life lightsaber, basically a more long-winded version of what I wrote here. I thought that this article was overly doubtful and takes you down too many dead ends (albeit, for the sake of understanding). My discussion here picks up where the only hopeful part of that article starts, at the end when they finally talk about containing a plamsa in a magnetic field instead of just shooting plasma out as jet, which would obviously be far to wasteful and resource-exhausting. Then they mention that a magnetically contained plasma might be disrupted by a kitchen magnet, and my first thought was "well obviously you'd want to contain a 10,000 degree column of plasma in an electromagnetic field that was at least stronger than a kitchen magnet."
Plasma Fire Sabers- I think this is mostly humorous, although I'm not sure yet. Its possible the people on this forum might actually be developing lightsabers, but its most likely just a bunch of l33t h4x0rz having a good time. Either way, the ideas they discuss are very interesting and I was suprised to see how many ideas that I had in mind that I saw discussed already. Hopefully they dont get angry that I'm directing people to their 31331 secrets and shut it down from public view.
KL's OOHYEA Collection - This guy had an amazing and huge collection of star wars props, costumes, and memorabilia. His lightsaber collection is beautiful.
Luukesabers - Thelightsaber.com - A great lightsaber site. Covers just about everything as far as the fictional lightsaber goes, even the extended universe stuff from books and comics. The lightsaber collection is rediculous. They've been holding annual custom lightsaber contests, mine will be entered in October for next year. Contest Info.
Blast-Tech - This site sells various parts need to finish replica prop lightsabers (such as the ones made from old camera flash guns).
Random Sabers - This place will actually machine a hilt for you if you send them a design. I dont really like any of the ones I've seen, but you might. They all have that episode I/extended universe/comic series look. Very nice though.
Lightsabers. - The Wikipedia entry. Wikipedia is THE source of reliable info on the net, and their entry on lightsabers is no exception.
May the Force be with you.