Just before Christmas I was looking around my almost-local Aldi store (next town along from me) and saw they were selling a "fisherman's hat". I don't fish, so almost ignored it, but I'm so pleased I didn't.
It's basically a baseball style of hat, but it has extra length at the sides and back to cover your ears and neck think Sherlock Holmes deerstalker, slightly). This makes it pleasantly warm to wear when it's cold.
But it's chief point is that it has 5 LEDs along the peak of the cap, and a concealed push switch underneath.
Evidently it's meant for your fisherman to see to unhook fish or whatever it is they do, and keep warm, in the cold dark night, but let me tell you, it's marvellous for seeing where you're going on the way up to the shed on a cold dark winter's evening, or when you're under a desk trying to see inside a poorly lit computer.
The Aldi offers seem to come around again every few months, or you could google for LED fisherman's hat and find something similar.
It's great!
Ian