This is why the discussions of pocket survival kits/altoids tin kits etc. is really so valuable. It has to be small enough to carry with you at all times, but still useful enough to provide the basic survival tools. That, with knowledge, equips you to survive.

I think it may have been Bill Merrill, author of "The Survival Handbook" who wrote words to the effect that the single most important factor in survival situations is having the will and determination to survive.