Google Wave
http://wave.google.com Google Wave is an online tool for real-time communication and collaboration. A wave can be both a conversation and a document where people can discuss and work together using richly formatted text, photos, videos, maps, and more. What is a wave? A wave is equal parts conversation and document. People can communicate and work together with richly formatted text, photos, videos, maps, and more. A wave is shared. Any participant can reply anywhere in the message, edit the content and add participants at any point in the process. Then