A couple of cool LED-light-related materials over at Inventables, "the innovator's hardware store:" Reflective Light Pipes and LED Light Diffusing Plastic Compounds.
The Light Pipes are like gasless neon tubes, but rather than using fragile glass they're made from virtually unbreakable acrylic with a co-extruded reflective layer. It makes me think of the umbrella handles in Blade Runner.
The Light Diffusing Plastic Compounds are simple-looking sheets that break hotspots up, giving you a nice, even glow. They're paintable, printable, and even laser-etchable.