For those watching Die Hard [1] on this Christmas Eve and unfamiliar with this plot device. 1980s version of crypto. [1] https://en.wikipedia.org/wiki/Die_Hard

For those watching Die Hard [1] on this Christmas Eve and unfamiliar with this plot device. 1980s version of crypto. [1] https://en.wikipedia.org/wiki/Die_Hard https://en.wikipedia.org/wiki/Die_Hard (As of March 2020, $870M of these bonds remain unredeemed)