Having different blogs (with different goals) is quite natural, but sometime you want to assemble them together.
Sometime you want to have a unique blog that mix them together.
This article explains exactly what I want to achieve.
I quickly get an account and write my first pipe named "FeedMix".
From the source toolbar on the left I dragged a couple of "Fetch-Feed" source and enter the blogs URLs. Beware that you must enter the RSS or ATOM feed URL. If you are unsure of what the correct URL is, you could use the "Feed Auto-Discover" source to get the valid URL of your feed. In the bottom pane the URL will be displayed.
When you're done with all your feeds just put a "Union" operator from the "Operators" toolbox on the left. Drag a line from the "Fetch-Feed" shape handle to the "Union" for each feed.
Then I would like that all feeds were ordered by published date. Also from the "Operators" toolbox I dragged a "Sort" operator, connected with the "Union" shape and then to the "Pipe Output".
The aggregated feed is http://pipes.yahoo.com/pipes/pipe.run?_id=dvDsX91P3BGyPKRCzKky6g&_render=rss (english and italian)