Originally Posted by
mechBgon
Have you seen any that are self-levelling, a la automotive headlights, to avoid aiming the beam above the horizon when the vehicle's not level?
Automotive headlights do not do this. They're fixed to the body. In general that's what you want, because if the vehicle isn't level, it's because the road isn't either. It causes trouble on hills, when you're cresting a hill your low beams are shining right into the eyes of oncoming vehicles.