Yahoo Pipes is "an interactive feed aggregator and manipulator". The service easily allows you and me to create a feed of feeds, sometimes known as 'life streams', though I like to call them: soup.
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The Yahoo pipes are a pretty impressive tool, but the once thing I find lacking is the ability to modify the output, in particular, I would really like to know the source of the feed when aggregating feeds. That said, if anyone know how - do let me know.
As always, let me know if you have any questions or suggestions.