Crypto-testament - Is it possible?

[HostFat]

I have a question to all crypto-guru here.

Is it technically possible to build a service ( or even a serverless/decentralised service, so that it can't be attacked/blocked/ddosed and without human failure attitude ) that give the possibility to leave a message somewhere and maintaining it encrypted until a certain date? ( example: bitcoinclock.com )
The service admins also must NOT be able to read this message until this date.

Example:
The user write the message and set a date.
Then the service give a link that the user can share everywhere he wants.

It would be good if the user is also able to stop it if it isn't needed anymore.
Example:
A soldier/spy that wants to leave a message to the community before a dangerous mission.
If he survive, he needs to be able to stop this crypto-testament to decrypt itself.

Do you like this idea?

[Stephen Gornick]

Is it technically possible to build a service ( or even a serverless/decentralised service, so that it can't be attacked/blocked/ddosed and without human failure attitude ) that give the possibility to leave a message somewhere and maintaining it encrypted until a certain date? ( example: bitcoinclock.com )

more info:
 - http://crypto.stackexchange.com/questions/606/time-capsule-cryptography
 - http://www.gwern.net/Self-decrypting%20files

[Andrew Bitcoiner]

+1 for teaching me something new and cool

[Red Emerald]

Math is awesome