(my photo)

the new runtime king for 1xAAA is the ThruNite Ti.

it just kicked the 82-hr-runtime Revo out of first place, because the ThruNite Ti has been tested at 125 hours on low (and it also does 60 lumens with a simple twist).

low beam is just enough for roaming around a very dark house, use on a moonless wilderness night, caving or during black-outs.

i bought two at $16 each and couldn't be happier.

HERE is a review i did on it over at CPF.

having owned hundreds and hundreds of 1xAAA 'lights, ranging from $1 to $250 (including a dozen of the above mentioned Fenix E01 and a few dozen Arc AAA), i'd call this new one a best-buy. while the E01 is still a great standard of comparison and is rated for 11 hours runtime (and can do much more), the beam tint is just plain awful (purple-green). and the quality of the current run of Arcs isn't what the old ones were.

seller seems like a good one too: Illumination Supply's sale page for the ThruNite Ti

and new models with different levels, and in different body colors, will be coming out shortly.

===

ThruNite Ti light are designed for Key chain application. It is the first AAA light with super-low Firefly mode (0.04lumens)

Features:
• Uses Cree XP-E R4 LED with a lifespan of 50000 hours
• Uses one 0.9-1.5V AAA (Ni-MH, Alkaline) battery
• 7.2cm (Length) x 1.4cm (Diameter)
• 20-gram weight (excluding batteries)
• OP reflector
• Reverse polarity protection, to protect from improper battery installation
• Made of durable aircraft-grade aluminum
• Premium Type III hard-anodized anti-abrasive finish
• Waterproof to IPX-8 Standard
• Reliable twist switch. Tighten for super-low Firefly mode (0.04 lumens), tighten further for max Output (60 lumens)

===

Cauldronborn2: that said, the super low level might be too-low for you, so an E05 or E01 might fill your needs best.