Light
There exist al lot of possibilities; from daylights to headlights to fog lights to high-beam headlights to working lights to mobile lights... All this in addition to the interior illumination that is also important to me. Recently, I saw even disco lighting on some offroad cars. Everybody has his/her preferences. Some people almost evaporate their batteries for a cool illumination. Others conserve the Amperes and prefer a rather 'romantic' design.
The adjacent list reflects my preferences. It is based mostly on rational ground although I have to admit that I potentially exagerated with my high-beam headlights.