Raindrop is a messaging application building on Apache's CouchDB which is used through a web interface. Raindrop works by collecting messages (currently emails and tweets, but more will be available through addons) and storing them as JSON optionally with attachments in CouchDB. They are then served to users with CouchDB's webserver so users can view them in their web browsers. By December 2009 there was a prototype for testers but no official stable release.
Raindrop was introduced by the Mozilla Foundation on Thursday, October 22, 2009. It is an exploration in messaging innovation being led by the team responsible for Thunderbird, to explore new ways to use Open Web technologies to create useful, compelling messaging experiences.
^Andy Chung, Bryan Clark, Dan Mosedale, David Ascher, Mark Hammond, and James Burke on behalf of the Raindrop development team (October 22, 2009). "Introducing Raindrop". Mozilla Labs. Retrieved 2009-10-27.