(Timelock algorithm deleted) --- That is a good way for locking it up for a while, but if it is really time sensitive, the use of parallel key guessing machines would stick a sock in this method. Here are some (non crypto) alternatives that you can use if you want to delay giving out the key after posting the cyphertext of the message: 1: Give the key to a trusted party, like your attorney to give out. 2: Find some way of getting the key lost via transport via SMTP daemons. If a host gets mail regularly via a UUCP connection, bounce it X times off that host. 3: Get the key "lost" in snail mail by this route. Mail it to a friend or a neutral party (Many copies if you may be snuffed in the process, to many people, and make "smokescreen" mails too). This would only work for messages with a short delay (24-48 hours). 4: (Very farfetched, but I am running out of ideas) Use a laser to bounce the key off a far planet or some body and the light travelling to there and back may give a decent delay. I do not know how you would get a coherent message back though. BTW: The time-lock idea sounds good, the mail list driver echoed it twice :) PS: Anyone have any better ideas for a secure crypto way of doing this? ;)