On the way home from work tonight, I had the radio tuned to the tail-end of NPR's Marketplace. Closing tidbit: Britain's Royal Mint flubbed the stamping of ~100K twenty-pence coins and issued them without a date. Presumably, that's a considerable loss of face. Why? Because the mint hasn't made that mistake since the year 1672.
That's right: About 337 years between making the same mistake twice. Roughly sixteen generations, in purely human terms. Kind of mind-blowing, really. And not a little humbling.