Say you want to smuggle something really thin and important, like small amounts of "prescription" drugs or an exploding Tic Tac. All you need is to think like a spy and use your hollow spy coin.

This is how the pros did it in the old days -- the KGB and CIA used hollowed out quarters and kopeks to smuggle microfiche, poisons and other tiny things.

Of course, you might raise eyebrows if you flash the 50 kopek piece (£20) or the Peace Dollar (£38), which was last minted in the U.S. in 1935, but if you go with the U.S. quarter (£11) your storage capacity will go way down. No current British coins are available, sadly. But Bond would still get away with it... [via Uncrate]