Yeah, I got a dome light from a Teggy at the wrecking yard for 5.00, went to radio shack and got 4 white and 4 blue LED's (make sure they are 12v or you will fry alot of $$) and keep in mind the higher the voltage says on the package the better (a car runs on 13.2 Volts not 12). I got the LED's a small wafer board (a circuit board with lots of holes), a conductor pen (a drawing pen filled with liquid metal (to draw the circuits) and took it home and soldered everything together, and then soldered wires to the contacts and put female terminals on them, (incase I need to replace it I dont have to cut and resolder).

I mixed up the LED's White-Blue-White-Blue.. You get it.... And it is very bright.

LED's- $12.00
Circuit Board- $3.00
Solder pen- $5.00
Total cost: 20.00

And it should last the lifetime of the dome light cover....