Last year, I tried various methods for combining RSS feeds and I found that none of them were very satisfactory. Well, thanks to a great post by Gina Trapani at Lifehacker, I learned how to combine RSS feeds using Yahoo Pipes. It is FANTASTIC. So, if you would like to be able to combine RSS feeds into a single feed, you can do that with Yahoo Pipes - and even add sorting and filtering criteria (for example, scouring a bunch of combined news feeds in order to find articles about a particular topic based on keywords). Check out the Lifehacker blog post for how to do filters; what I have done here is written out instructions for how I was able to create a simple combined RSS feed for my own blogs.
First, go to Pipes.Yahoo.com. You will need a Yahoo log-on in order to create a Pipe and save it. The Sign-In link is in the upper right-hand corner, and if you do not have a Yahoo account, you can easily create one now using the Join Now link.
Next, click on Create a Pipe.
Drag the Fetch Feed module (filed under Sources) into the working area.
Then add URLs for the feeds in the slot provided; click on + to keep adding feeds, and click on - to remove a feed. Be careful if you see an exclamation mark: that means there is some kind of error in the feed address that you entered which you need to correct.
When you are done adding your feeds, drag the Sort module (filed under Operators) into the working area. Set your sort criteria (I am sorting by publication date in descending order, that is, newest first). Then connect the modules so that the Fetch Feed box connects with a pipe to the Sort box, and the Sort box with a pipe leading into Pipe Output. You can then click on the Refresh link in the bottom window to see the results of your combined feed!
Now, give your Pipe a name by typing in the title tab and then click OK.
Click on Save and then Back to My Pipes.
You should now see that pipe listed in your list of pipes - you can click on the title to be taken to the display page for that pipe.
From there you can Publish your pipe: just click on the Publish button. Then, to get the RSS feed, click on More Options, and choose Get RSS.
You can then use that RSS feed in a feed reader, or use it to create a dynamic widget of the compound feed in order to display it in a blog post or in your blog sidebar - it's an RSS feed, like any other RSS feed... except that you CREATED it with YahooPipes! :-)
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