I've heard of the road flare option, but I understand they have some nasty chemicals that I don't want anywhere near my food or my face, etc.

Anyway, I wouldn't be carrying a road flare in the situation described in the original post (dark, you are cold, wet, and tired, and you need a fire NOW). If I got to that point, then that means I lost my main pack (or car) and I'm down to what's on my person (e.g., pocket or fanny pack).

On my person, I should have at least two of the following:

Mini Bic
Ferro rod and striker
Vaseline with cotton balls

As long as I can find fuel that's not super wet, then I feel confident I can start a fire with those items. Anyway, this is something I need to practice: starting a fire when it's pouring raining and shelter is not established yet.