ReadFit is a system that aggregates contents from different social news sites and presents the links in a very simple HTML page, sorted by a custom ranking function.
You can read more about ReadFit in the Design Doc: https://docs.google.com/document/d/1jRJj4mWwFVH0ZvAXNgt7hsI41vdL3-zuLn50xMI_zKE/edit