Note this post by Brett Tabke, the admin of WMW:
"> if you run a site from your own machine.
It is *not* just like p2p. It is a proxy cache. Opera's proxy cache, keeps a copy of the object until it is replaced or updated on your machine. Your machine only fesses up one copy of it to the proxy cache. Everyone else pulls from the cached copy. Thus, it is not a true "web server". You could serve a picture a million times off your feed, and all you do is send one copy to the proxy cache server. This is *really* what Opera Turbo was testing in the beta tests (the proxy caching mechs).
It has been 12hours since the feature was introduced. Has mozilla ripped it off yet? 
> any developers
You think? Just look at the huge numbers opera has attracted to it's widgets: http://widgets.opera.com . that is an awesome developer base".
Source: Opera about to "reinvent the web"
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opera unite site:webmasterworld.com