OK, maybe now we should just call is Wave . As I talked about a few years ago in my blog, I really enjoyed using Wave for interacting with family and friends, and also experimenting writing Wave Robots hosted on AppEngine. Those good times have ended :-( Fortunately, the Apache Wave incubator project provides the code and directions for running Wave on your own servers. If you are lucky, installing Wave is as simple as: git clone git://git.apache.org/wave.git wave cd wave ant compile-gwt dist-server ant -f server-config.xml ./run-server.sh The default data store is the file system but you can use MongoDB instead. After you have started the server, you can use two different web browsers (e.g., Firefox and Chrome) to create two different accounts using the Register a new account link on the right side of the welcome page. After logging in under two accounts with two web browsers then create a new note under one of your Wave accounts and invite the other user account to that note....