At 7:04 PM 11/15/1996, Hal Finney wrote:
From: ph@netcom.com (Peter Hendrickson)
A well shuffled deck of 54 cards has about 237 bits of entropy. This is easy to use: the program asks the order of the cards, converts this to a string, and runs it through a one-way hash. (Entering the cards is a bit of a nuisance. Is there an easy way to have them read automatically?)
I heard that Bruce Schneier has devised a cryptosystem based on a card deck for a future book by Neal Stephenson. It is supposed to be simple enough for a person to use manually, but complicated enough that it can't be broken by computer. Your idea of using cards as a one time pad is somewhat similar, maybe, although I think Bruce's was designed to be useful for long messages, providing computational rather than unconditional security.
I, for one, am dying of curiousity. When I asked him about it, he said he would disclose it "soon". Peter