This Message Will Self Destruct (TMWSD) "....is a secure messaging service where messages sent are encrypted, securely transferred, and automatically deleted when they are retrieved." Brilliant.
A little more detail from the site:
"TMWSD is a secure, auto-deleted messaging service.
This means two things:
- We encrypt your message before we store it.
- The first time the message is retrieved we delete the encrypted content.
We didn't stop there, however. We added the ability to restrict access by password. You don't need to worry about your password either, because in this case we never actually store it. Instead we hash it using a heavy-duty hashing utility (bcrypt). As an added bonus, if you provide a password we salt the encryption key with it for even more security. This means that without the password no one can decrypt your secret message, not even us."
I'll leave the reasons you'd like to use this service for you to ponder. :)