The one time I was out on a boat at night, we were running some trotlines in a lake. The best light was my Aspheric Modded Maglite, the tight beam really made it easy to pick out our markers in the dark. Like others said, the spill from other lights messed up our night vision too much. I'd probably go with something like a modded UniqueFire UF-1405. Swap out the emitter with an XP-G2 and you should be set.