3) Polarized Film - This would've been the home run, if materials were readily available. One enthusiast procured some of the polarized film used in the construction of LCD displays. By applying two, cross-hatched, layers of the polarized film to a standard saber blade, light was re-directed from a standard saber blade. Basically, instead of moving straight-out from the core, light would hit the polarizing film, bounce, and only exit at about a 90-degree turn. This meant that the center of the blade always appeared dark, while the edges appeared lit. Sadly, the film proved very expensive and was only available in small sizes - so at best, there were seams in the blade. The material is typically only sold-to/manufactured-by LCD suppliers, so it's not readily available to saber enthusiasts.
Oooh, do you have any pictures of this?
