I just received my NiteCore EZ AA and can confirm it DOES fit in an altoids tin. You'll have no trouble with the AAA lights as every one I have fits in the tin. The EZ AA is my first single AA light so it is the only one I can comment on. Although I did pick up a single AA tube for my Fenix 2 AA light. I suspect it will be a little too thick to fit and might only fit diagonally for length. I will confirm when I get home and get to try.

The Fenix 1 AA will NOT fit in the altoids tin. It might be a little too thick and it IS too long.

The EZ AA is pretty nice. The high mode is very bright and the low is plenty good for most things.

For an Altoids kit, I'd go with the cheap Fenix AAA light. I've had the similar-performing Arc AAA-P on my keychain for years and it's enough light to get things done and the battery goes for a long time. I wouldn't use an alkaline though, especially if it will be stored for long periods. Use a lithium. It'll never leak.

I gave up looking for a good compact single AA flashlight. And went with single AA and Photon ReX in my mini kit. ReX actually can recharge from any battery cell and is very versatile flashlight. The EZ AA looks pretty nice though.

That ReX is kinda clever.

A while back I had an idea for a rechargable keychain light that would primarily be intended to charge via USB power.

I plug a flash drive plugged into my work computer in the morning and then take it with me at the end of the day, so the same habit would keep the light fully charged. I imagine many people do the same.

It was actually made in 2005: http://www.engadget.com/2005/05/10/ion-technologies-flashlite-usb-thumb-drive-with-flashlight/ Some available on Amazon now. Like this Victorinox for example: http://www.sureneeds.com/5301g2.html