Have you ever wanted to send a message to someone, but you did not want it to be stored in permanent form in email? There is now a website that is addressing just such an issue.
OneTimeSecret.com allows you to type a message and send a URL to someone. Once the URL is displayed once, the message is gone forever.
Some good uses for this would be the sending of passwords or other sensative information (as suggested by killerstartups.com .
I double checked that the website runs on https only (which it does), so that makes it safer for sending sensative data across the wire.