I did some experimentation with a little 2 x AAA Underwater Kinetics flashlight which I use as a keyring. There is some empty space between the two cylinderical AAA batteries and I decided to stash a match and a needle in there. The bezel turned out to be big enough for two Micropur water purification pills.
I admit that they might not be the most useful emergency items for such an urban person as myself, but I just like the idea of having some backup for everything and I also like the general concept of “install and forget it”.
At least it’s not as heavy as this person’s every day carry collection.
I’ve always been a bit of a gadget freak, but this whole survival theme was sparked by my earlier article Safety gear for the chronically paranoid and perhaps also by the Open Water movie which I saw a few days ago.
EDIT: I just learned that one of the active ingredients of Micropur, chlorine dioxide, is a highly reactive chemical that can cause violent explosions at gas concentrations of over 10% and it isn’t compatible with ammonia compounds either (batteries). Another mad science project gone wrong 
Posted by api in Outdoor pursuits