Opera Unite. Opera’s big announcement: a developer preview (“labs release”) of their new web-server-in-your-browser feature, Unite. Includes an Opera-hosted proxy to help break through your firewall. The web server can be customised using server-side JavaScript running in an Opera Widget.
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My first reaction is... am I really waiting for this. I don't like that it only works in an opera browser. Flock was slow doing lots of stuff... this will be as well. Chris Messina has a good post about it with some very critical questions http://factoryjoe.com/blog/2009/06/16/thoughts-on- opera-unite/