The time vault suggestion resembles one from Tim May in 1993. Rivest Shamir and Wagner also addressed time vaults by requiring a computation (resistant to parallel calculation and of reasonably well-defined length) to decrypt the message. under http://theory.lcs.mit.edu/~rivest/ -- ############################################################## # Antonomasia ant@notatla.demon.co.uk # # See http://www.notatla.demon.co.uk/ # ##############################################################