Mozilla has announced a new open-source, experimental communication platform called Raindrop. Built around the idea that "email isn’t fun anymore," the service is meant to act as a mini Web server to fetch your conversations from different sources (email, social networks, blogs and more) and then intelligently sort them so that personal messages "bubble up" while minor messages and notifications are pushed to the sidelines.
The idea is to separate emails from people you actually know or conversations in blogs and social networks you may want to participate in from, say, online promotions, countless newsletters and Facebook notifications.
It shares some similarities with Google Wave in its attempt to re-imagine web communications from the ground up and the ability to extend functionality through an open API -- thus many are already calling it a competitor. However, from what I can understand looking at this video, Raindrop is more about streamlining conversations and making sense of the huge influx of messages coming our way, whereas Google Wave seems to focus more on facilitating real-time collaboration within a (preferably modest-sized) group of people.