I've decided I'm carrying at least one fire starter on me at all times. For the ONE fire starter that will be on you at all times, what's your ONE choice?

For the last month or so for my ONE fire starter, I've been carrying around a tiny ferro rod, cotton balls, Burt's Bees lip balm and a folding knife. All items were already there except the tiny ferro rod. Also, everything has multiple uses besides the tiny ferro rod.
http://firesteel.com/products/FireSteel-Pup.html#

That setup is more efficient for me than a mini Bic, which is my next best ONE option.

Some generous ETS community member let us know about the Neo Azen lighter:

http://www.sportgearusa.com/lighters.html

Reliable, one-handed operation, etcetera.

Outside the city, if limited to one I'd carry one of my firesteels (am also a fan of www.firesteel.com). For tender, vaselined cotton balls.

In the city, a firesteel would be awkward for lighting peoples cigarettes.

In the city I have a CountyComm Split Pea lighter. Other places, I'll typically have a firesteel, REI Storm Proof Matches, a Bic and a Peanut lighter. Only one? I'd say a Bic.

For me it would be between a Ferrocerium rod and a BIC. I like them both equally for different reasons.

With this in mind, I always have a BSA Hotspark ferro-rod on my keychain and a BIC lighter in my jackets/coats. I figure, if I'm going outside I've probably either got my keys on me, my jacket on me, or both.....therefore, I've always got at least one method on me.

(I've also got a magnifying glass in my wallet, so you could count that as a back-up method.)

My EDC is a mini-Bic.

I carried it for a long time without an significant leaking or issues but I've taken to wrapping a blousing band around it a few times. It isn't evidence based but I suspect that the band riding under the gas lever may help prevent leaks. The band, along with pocket lint and the cotton pocket material itself, provides a reserve of tinder.

Every two weeks or month I pull it out and test strike it and check flame height and condition to make sure I have a decent reserve of fuel. I keep spares at home but one lasts many months, well over a year.

I think years is closer to it. I wrote the month/year I first used the Bic I'm carrying now but the writing wore off. It's been that long.

Yes, I know. I'm not going to boost my reputation as a rugged frontiersman pulling out something as pedestrian as a mini-Bic and kindling a fire in seconds without theatrics or arcane techniques, I may have to relinquish my Kit Carson club membership card, but it works.

If I wander off the beaten path I stuff a second one in a pocket. A ferro stick and tinder, mag block/ferro stick, or matches sealed into a bindle, makes a third.

But for simplicity, ease of use, effectiveness, speed of getting a fire lit in lousy conditions with poor fuel, weight/size, and reliability the mini-Bic wins. For about a buck a piece they are a bargain.

Napalm

I've always wondered, does somebody have a good way to tell how much fluid is left in a mini Bic? If not, then I'll just have to label my mini Bics as "new" and "not new".

I carry a light pretty much all the time, either a standard Zippo or a Zippo upgraded with a Z-Plus butane insert. I also have a Country Comm Stainless Pea Lighter on my key-chain.

If I had to pick just one fire starter to carry with me in the field it would be a Spark-Lite kit, specifically one of the metal ones. So far, Spark-Lites have been 100% reliable for me in all conditions I have used one.

Shine a light behind it and you can see the fuel level through the plastic. It works better with the lighter colored models than the darker colors though, which is why I stick to orange/yellow/white bics.