These are very nice lights:

http://www.petzl.com/us/outdoor/headlamps/tikka-zipka-series/zipka-plus

This is not a single-AA lamp (it's 3xAAA), but it is very small and versatile. It would not fit into an Altoids tin, but it is very pocketable. It can be used as a headlamp, handheld, attached to various objects, etc. I have the earlier version Zipka2 ( http://www.petzl.com/us/outdoor/headlamps/compact-headlamps/zipka2 ), but the new Zipka-Plus2 looks even better.