While testing the latest version of Bitwatch, I was shocked to see that another puzzle transaction has been found:
and sure enough it has:

For those who don't know about the Bitcoin puzzle distribution, back in 2015, a mystery operator deployed bitcoin across the keyspace: https://www.blockchain.com/explorer/transactions/btc/08389f34c98c606322740c0be6a7125d9860bb8d5cb182c02f98461e5fa6cd15
More info here: #683489
Yet another reminder to use multisig!