LED's are being sucessfully used in many cases as brake and tail lights. The new LED's are now brighter than almost all conventional incandescent bulbs and require no mettalic reflectors. LED's are available in a wide aray of beam widths from 10 degree narrow to 150 degree wide angle. The best part about using and LED aray for your tailights is that they have nearly 100% usefull light because there is no filtereing throught the rear red lens, it is a red light source. Also, a 100,000 hour life and no heat along with minimal power consumption are bonuses as well. You can strobe LED's for emergency use as well. The new Nicchia LED's are putting out about 15cd of light EACH, try to look into one.