I work in an office environment - no suit coats - and prefer to have the light with me in my pocket - like a keychain setup.

My preference is something built around a AAA battery. The thinness of the package makes it tolerable in my pants pocket. I carry an Arc AAA LED light which I like, but don't know what the best offering are these days in that kind of package. I prefer the anodized case over something painted because it rides with a pocket full of keys every day and hardly looks used. Amazing.

I really REALLY like Fenix's single 123 lithum battery LED lights - amazingly powerful for the size - stunning for its size, but find the package a tad too thick for my pocket.

I want to have the choice of at least two settings ... (1) a little light for a long time, or (2) a lot of light for a short time ... in the same package. Is that too much to ask?

A light is as much of a must as the knife.