AideRSS for Firefox extension harness the power of PostRank to score, filter and track performance of any RSS feed directly within GoogleReader. Now GoogleReader users can reclaim their time with a single mouse click to find the best content, boost their productivity and stay on top of the news.
Once you install the extension or just the Greasemonkey script, AideRSS adds the PostRank value next to the title of each post and lets you filter the most popular posts. If you select a folder or switch to the “all items” view, AideRSS adjusts the ranking values based on the context. AideRSS also integrates with NewsGator and it lets you subscribe to the most popular posts from a feed
Features: When browsing in folder or tag view, hit c to enable visual grouping of stories from same source. In expanded or list view, hit x to hide or unhide PostRank filtered stories.
Source:→ Google System