I have been doing a good bit of walking early in the AM before it's light or after dark at night and the little 1 AAA Streamlight Microstream has become my go to light. The Microstream is easy to carry in a T shirt pocket and weighs almost nothing. Run time on a AAA eneloop is over 3 hrs. It's only 45 lumens which is not much by today's standards, but is plenty for my purposes. Most of the places I walk have street lights so I don't really need a light very often in these areas and I don't like to use any more light than I need on unlit trails as to not attract attention or disturb anyone in near by homes. I use momentary almost exclusively to give a burst of light to check the stretch of trail ahead and then shut it off to try and keep as much adapted night vision as I can.