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.