You could sign the data. Distribute the public key far and wide. Destroy the private key before you die. The advantage of this approach over just the hash is th

You could sign the data. Distribute the public key far and wide. Destroy the private key before you die. The advantage of this approach over just the hash is that you can sign an unlimited number of files and can verify them all with just one public key. It is all authenticated by your identity. If your signature scheme is broken over the years then that means that people can tamper with the files. So you can use different schemes just as with the hashes. Who is going to be able to verify your identity after 500 years and/or have a verified copy of the hashes? Without the concept of identity, it's all just a bunch of bits.