The Editable Web is definitely the next big thing, but this is too narrow scoped, I think.
There's a company called Tomodo (where I work) that allows you to modify any website and publish it as an independent one. Rellay cool stuff. Check it out - http://tomodo.com/
That is an interesting idea, but what is the value of doing so?
Sadly none of it works on iPad. Cool though. Telerik make some cool stuff.