Some of you may have heard of "The Amazing Randi", a magician who offers various million-dollar prizes to anyone who can prove psychic ability (no winners yet).
Recently, he placed a mystery object inside a specially-constructed box, and challenged any psychic
to use his or her "remote viewing" abilities to tell him what was inside the box.
Obviously, he could've just "changed" what was in the box, after a psychic correctly "viewed" the item. So, to be fair, he published a "secret code" that revealed the identity of the item, so, in the future, he could demonstrate that he had not switched the item.
A cryptographer analyzed the code (cryptographers refer to them as "commitment strings"), and correctly determined the identity of the item. He graciously declined the $1 million prize, and wrote about it in an interesting blog entry
The really cool part is that he ties it all in to voting machines, which I know we've discussed in here before. He describes how cryptography can be used to make our voting machines much more secure, but that, ultimately, it's useless -- because the voting process must be able to be understood by a layman.
For several years now (long before the present debate on the subject), there have been cryptographic election systems proposed that provide a remarkable range of provable security properties, including anonymity, publicly verifiable outcomes, the inability to sell votes, and so on. And yet election officials and the vendors of electronic voting machines have almost universally ignored them. Why? Largely because these protocols are practically incomprehensible without (or even with) specialized expertise. The first requirement for a democratic election is that voters understand and have confidence in the outcome. The crypto-based voting systems proposed thus far by and large fail this test from the start. Voting, like psychic debunking, is first and last a human-scale problem.
Full text: Crypto.com