From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <9124780337ba5fbd0bd5d14cff2fba5a@juice.thebigchoice.com>
From: matt@proweb.co.uk
To: 9fans@cse.psu.edu
Subject: Re: [9fans] cryptographic signatures & factotum
In-Reply-To: <559b5ec89e2cfd991a8152e0ceddc88c@snellwilcox.com>
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Date: Fri, 12 Mar 2004 00:27:16 +0000
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as well as the other good suggestions there's also port knocking

http://www.portknocking.org

which you can use like a combination lock 

m