I second PaulR's appreciation of the ARC AAA flashlight. It is my current keychain light. I consider it the near perfect keychain flashlight (only because nothing's perfect, right?).

However, I hesitate on recommending this fine flashlight to non-flashaholics due to the high price tag and long wait time to receive it. The average joe on the street might miss it's fine qualities and not appreciate the price and lead time.

That said, the Gerber Sonic AAA had keyring duty till the ARC arrived. Unless ultimate size and weight are an issue, the Sonic is arguably a better keychain light than the Photon or Inova. My biggest gripe with the Sonic is the exposed LED and the not-so-tight tailcap. So far the LED has not been damaged, but I still worry. Also the exposed LED creates more "spill" (180 degrees) than I like for discreet use. For the loose tail cap (an unfortunately common trait) I ordered a second O ring and butted it up against the existing ring. This provided a good amount of snugness and likely improved the water resistant properties as well. My sonic is now doing duty in my nightstand.

If you really want to immerse yourself in flashlight geekdom, check out:

http://www.candlepowerforums.com .

It is a good group of folks that have an illness only cured by more LUMENS!!!

I still plan on pickin up a red LED Inova to hang on my short-wave radio's lanyard. This allows me to check the dial at night without distrupting my wife's beauty sleep.

Good luck, TR