If you have never thought to yourself, I can't wait until the day I send someone a note that says, "This message will self-destruct in 30 seconds," then you should both check yourself and have that thought now.
Privnote was devised for the spy in you, or at the very least, the person in you who has a really juicy secret on their hands that they do not want to be traced back.
Simply go to Privnote's site and type in your super secret message, and they'll give you a link to send to your recipient. Once they read it, poof, it's gone, and it can't be accessed again. Stealth.