Built a new PC not long ago and I went crazy buying all kinds of lights(neon, neon wire, leds lazerleds, uv lamps, plazma(cool)) from a bunch of suppliers(xoxide, coolerguys, crazypc, not to mention most of the main sources), but there has to be a 1000 suppliers out there.
the neon wire is very cool(to touch also). one mod is to put it into ur keybd, requires dissasembly, ha.
but they have all kinds of lighting stuff, only ur imaination limits u. short, long, almost every color(some cost more), but from 3-20 bucks it's kinda cheap.
Althought u do have to be careful with the plazma, neon or uv, cause it's high voltage and the wire installation can not be cheap or u'll get shocked, I know, this stuff will arc seriously if you have any raw wire/connector exposed in close prox. of grounding, so be carefull.
Not to mention some of the crazy lighted fans u can get, some even type out text like a banner, ha. I went with a lot of uv sleeving and lights for that glow in the dark effect. ha, have fun.