OK, I just founf a few interesting things on eBay Here and here So I was wondering... This is on real glass, but I'm presuming it's just an etch on glass ad the light is being shone through the middle of the glass.

So could I do this same sorta thing on plexi, and if I wanted to just have the inside of my case UV'd how would I be able to get the light through the etching without having a CCFL inside my case?

the best way to do that would either:

use a dremel, to scratch the surface
use a router to make a groove (looks nicer)
buy some of that platic film that looks smoked, and cut it into the correct shape.

then eiter use leds or a ccfl to light it up