Poor Man's Time Release Crypto

[Eric Hughes <hughes@soda.berkeley.edu>]

An obvious but very important point about any time release protocol
can be observed in the following one:

   1. Publish some non-random encrypted data.
   2. Wait.

Computational increases will eventually make cracking the code
feasible.  Your secret will be revealed, but you just don't know when!

Technological progress puts an upper bound on the amount of time a
secret can remain secret.  Likewise, Diffie-Hellman is forward secure,
but only until taking discrete logs in the chosen ring is feasible.

Eric