They go red on brakes... I'm thinking about making either a flashing blue one for shows to go with the neons on the car (programmable) or to make it flash a number of different colours, or just ultra violet Haven't quite decided... all will cost me about $280 to $300...
There is an easy way either through me or MLT15E (also on the forums) but I have yet to actually sell one cause people get scared at the price