Obtaining autographs are a common way of showing appreciation for a celebrity, but the less than scrupulous try to take advantage of this. Autographs are often forged and sold, much to the consternation of collectors or the originator. Basic cryptographic principles may be applied to keep this form of appreciation free from corruption.

A celebrity simply writes a personalized message, then cryptographically signs it using their private key. The recipient can easily confirm the validity of the signature, and sleep easily knowing their autograph is genuine.

Since the autograph is personalized, the market declines immensely. Who wants someone else's autograph? As a result, autographs once again become a pure expression of interest in a celebrity, and no longer a commodity.

Alternatively, the celebrity could sell these personalized autographs for a high price, with no counterfeiters to eat into their profits.
-- Aq_Bi, Oct 12 2013

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