If it's text only, there's also zerobin (http://sebsauvage.net/wiki/doku.php?id=php:zerobin) that has a lot of features and the added bonus of not storing the key on the server (it's using the anchor part)
Also created something similar a while back for fun, except for short text messages with the option for encryption in Javascript using an implementation of blowfish. It saves the data encoded (or encrypted) as part of the url.
Source with demo: https://github.com/alfg/jot