The Last Chance Box – I believe the Czech Boy Scouts came up with this one. The idea is that you take a small sealable box (eg. a tea tin) and you fill it with things that might come in handy.
A non-exhaustive list: buttons and thread, a toothbrush with the handle sawed off, a pencil stub, a poem, loose change, a bus ticket, a calling card, a teabag, safety pins, packets of sugar, a pair of dice, band-aids, alcohol swabs, spare contact lenses, a razor blade, spare allen keys, a plastic bag, contraception, a pocketknife. I myself have never been a Boy Scout and anyway am not nearly organized enough to have a Last Chance Box, but the idea is a good one.
—excerpted from A packing list for any adventure