Riding the trusty commuter bike home today (in the dark) and my totally reliable headlight goes dark in the first hundred yards. Everything worked perfectly this morning --front and rear lights fed from a dynamo front hub. I stopped to fiddle the wires a bit but they were solid and the rear light was still working. So maybe it burned out. I still have a rear light and a very bright rotating red light on the front wheel that has fresh batteries and never fails.
Half way home the tail light goes out. Weird, but the load differences, ..maybe the tail light is now burnt. Can't see very well now but that reliable, super bright rotating wheel light means others can see me. A mile from home the rotating light goes dark. That light has never failed me in 10 years -EVER! Three separate lights on two separate systems go out within twenty minutes. I have a puzzle to solve this weekend.