How to Make a Padlock Shim. Have you lost the key to a padlock? You could call a locksmith or cut the shackle, but you may be able to quickly and easily open it with a shim, a thin piece of metal that you slide into the locking mechanism.
Camping Hack: How to Make Fire With a Lemon (Fact or Fiction?) - I thought this was a pretty clever, although not terribly practical idea. While you may not have these types of items lying around (zinc nails anyone? :)), it just goes to show you what might be possible if SHTF.