I know we’re never going to see something as fun and pointless as a message that destroys itself after reading it, but this is close enough.
You post your note, and you receive a link. Once someone clicks on the link, the page is gone. Not as dramatic as a piece of paper shriveling up, but it serves the same purpose, albeit a tad bit less secure 😛

Its a bit of fun, check it out: Privnote.com