check out the eGear PicoLight
But it doesn't run on a single AA per the original post.
I have an Arc premium. While it is built like a tank and has service me well as an EDC light, it is certainly not the brightest light I've seen, but may be about as good as it gets for a single AA.
I bought a Fenix P1D's for my own kit (not EDC) and another one my wife's barn key chain (for safety - it also has a Storm whistle on it).
The P1D runs on a single CR123A - not a single AA - but they are fairly small AND they are AMAZINGLY BRIGHT and very VERY tough (anything that can survive this long on my wife's barn key chain has GOT to be tough - it gets really abused). It has three settings. Low will run for 20+ hours on the low setting. High will only run for 2.8 hrs but during that time it is stunningly bright for such a small flashlight.
I'm talking bright - as bright as my 4AA Streamlight ProPolymer. Maybe brighter.
The reason I bring it up is that the other night I walked out to the barn with my wife. Since I wasn't wearing my barn boots I needed a light to avoid stepping in canine-generated land mines (sorry about that image). I pulled out the EDC Arc-P to use that, but then my wife turned on the Fenix P1D ... and the difference was stunning and almost embarrassing. I shut off the Arc-P and used the P1D instead.
Yes, the Arc-P would have been better than nothing, but in all honesty it really doesn't produce enough light for me to work (or avoid objects on the ground) at night.
BTW, I wish the P1D had a tail-end switch for easier one-handed operation. It can be turned on one-handed, but it is awkward.
Overall my favorite "survival light" would be my Princeton Tec Rebel EOS headlight. Its fairly small (not Altoid size though), one-handed, BRIGHT, 50+ hours on low, and it frees hands for work. I don't have one of Doug's eQ multi-light, but it might be work checking out. There's nothing quite so useful as a good headlamp.
A lot depends on the size of kit you're packing.
Ken