Streamlining my RSS feeds - I want a SELECT DISTINCT

This post by Matt over at Peer Pressure reminded me of an improvement I'd like. I think a great improvement for RSS aggregators would be the ability to act like a SELECT DISTINCT does in SQL scripts.

For example, my aggregator would look at my list of 50 feeds (each of which has about 10 updates per day, so about 500 posts total), and group the posts so that I'd only see "Oracle faces old friends as foes" once with an "10 similar posts" note, and I'd only see one "Microsoft introducts Live software-as-a-service" with a "16 similar posts" note, instead of seeing each of these same/similar articles 29 times spread throughout all of my different feeds. I bet this would make it so I was only skimming through about 200-300 posts per day maximum, instead of 500.

It's not really addressing getting the cream of those to rise to the top, but at least it's dramatically improving the signal to noise ratio. If you could collapse the related sections on 'meme'orandum and apply that concept to your own personal RSS aggregation, that would be getting towards what I'd like to see. Thoughts?