PGPnotes.com is a free web service that allows you to send confidential notes using the internet. It's quite easy to use and no registration is required.
You write a note in the "Message" field, specify the password (generation password is available) and the size of the key. Then public and private keys are created, encryption is performed and encrypted text is sent to the server. PGPnotes.com encrypts your note and gives you unique link to send to recipient. Messages are self-destructed after reading.
Filling your email in the "Destruction notification email" field you will get notification to that email when message will be read by recipient.
PGPnotes.com uses the Pretty Good Privacy (PGP) technology: user creates a key pair: an open and a private key. When generating keys are given by their owner (name and email address), the type of key, the key length and its validity. The public key is used to encrypt and verify a digital signature. Private key - for decoding and creating a digital signature. Everything happens in the browser and no information is sent to the server until it is encrypted in the browser.