My perfect headlamp is the Petzl Zipka. It attaches to anything - had it on the top of my trekking pole the other day. I put it on the ridgeline of my hammock to read. It's not the brightest but it's adequate to the tasks I have for it and takes three triple A batteries rather than something proprietary. As a backup I take a Photon microlight.
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"In the beginner's mind there are many possibilities. In the expert's mind there are few." Shunryu Suzuki

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