Under Sources, drag and drop “Fetch Feed” to the Pipes canvas. Under Operators, drag and drop “Filter.” Then fill one of the two feeds I provided earlier in the feed field, and choose “item.description -> does not contain -> your username” as follows:
Don’t forget to link the pipes like in the above screenshot. Save your work, then click on “My Pipes” you will see your feed that you just created. Hover over it, and click “view results.” There you will get an RSS icon that links to that feed. Now all you have to do is feed into one of the many auto-tweeting services like twitterfeed or hootsuite.
Here is the result: