Just as Google Wave represents an attempt to imagine what e-mail would look like if it were invented today, Mozilla's Raindrop represents an attempt to imagine a more modern communication client.

Developed by the team that created Mozilla's Thunderbird e-mail client -- good desktop software with the bad timing to emerge just as Web-based e-mail services were taking off -- Raindrop recognizes that the diverse range of communication channels -- Twitter, IM, Skype, Facebook, Google Docs, E-mail -- would be more useful if presented in a unified interface.

Google Wave is, as Google puts it, "a product, platform, and protocol." Raindrop is simply a product and platform.

Available at this point only as development code from Mozilla Labs, Raindrop aims to help users manage the messaging they already receive. Once enough people begin sending and receiving Waves, the Raindrop team plans to look at ways to integrate Waves into Raindrop.

"Raindrop is an effort that starts by trying to understand today's Web of conversations, and aims to design an interface that helps people get a handle on their digital world," the development team explains in a blog post. "At the same time, it creates a programming interface (API) that helps designers and developers extend our work and create new systems on top of that data."

Google Wave also supports integration with other communications services, such as Twitter. So there may be some competition over which brand of water -- Wave or Raindrop -- better quenches users' thirst for easier communication management.

Much of Raindrop's filtering functionality is already available in e-mail clients like Apple Mail and Outlook, which allow for the creation of rules that file messages in different folders and can handle non-e-mail protocols like RSS.

But there's certainly an opportunity for the Raindrop team to make filtering easier to use and functional across a variety of channels.

As with other Mozilla open-source projects, the Raindrop team is encouraging interested developers to participate and contribute code to improve the project.

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