I use a Fenix LOD clipped to my hat. On high it's brighter than most of my headlamps, waterproof and less than .5 ounces without a cell. With this I can do away with the weight and bulk of a headstrap altogether providing I bring along a hat with a brim, which I always do anyway. It uses AAA cells which are available anywhere and with 3 levels I can do anything from camp chores, reading or even night trail running with just enough light. It's one of my favorite pieces of gear.

One caveat: In winter when the days are short I usually bring a full blown headlamp with the LOD as a backup. Or when bushwhacking after dark is a possibility. No one light does it all.