I just found a company in India that makes calcium carbide headlights specifically for bicycles. Have any extreme Retro types here tried one? I used a normal cap lamp when I was a student in mining in the early 70s. The "Gee Whiz" factor would be incredible on Club night rides, the amount of light is good, and you could warm your hands on a cold day. The Indian company even makes indoor carbide lamps for people who are way off the grid and do not want to support the oil industry. The JKDay company by the way.