I just played with JSonduit, and was able to make a data feed from the JSMag blog feed in about 6 minutes.

http://jsonduit.com/feedinfo.html?id=7q6 takes you to the feed info, with the ability to create a custom widget for display on a site.

With some slightly stronger authoring tools, this would allow ‘common folk’ to identify parts of a page they’d like to be accessed, create a ‘feed’ from them, then pass just the feed to developers for processing.  As it stands, it’s still a bit more of a geeky tool, but useful nonetheless.  It’ll be interesting to see what people use this for.