Spy is a search engine for – as they call it – social media conversations. It is powered by Google’s App Engine and indexes the services Twitter, Friendfeed, Flickr, Yahoo News, Google Reader, Blogs and Blog comments. Just enter any keyword or phrase in the search box and select the amount of results that should be displayed.
The service displays keyword trends and examples like iPhone, Obama or Superbowl that can be clicked on to perform the search as well. Spy will search its index for occurrences of the entered or clicked on keyword. It uses Ajax to update the search screen automatically. Search results are ordered by relevance.
The service makes use of two display modes. Poster mode makes use of speech bubbles displaying user avatars and the messages.

While Spy is not the most thorough search engine out there it can be used for several purposes. It can be used to read reactions on blog posts or follow conversations about recent events.

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To bad the user cant say in with blogs he, the user, want, to listen in.