There's an immense amount of knowledge, insight and entertainment in the feeds I follow. Using Reeder.app on my iPhone, and Google Reader web or Reeder.app on my desktops, I learn something new every half-hour or so. I share some of the stream via Pinboard (archival), app.net, twitter and wordpress (archive and indexed into my custom search).
Works pretty well -- but it could be better.
I'm skimming the surface of the knowsphere. There's great material below, sometimes in once beloved blogs that have gone silent. We need a way to dig it up.
That's someting old-Google might have added to Reader. Using signals like links, non-spam comments and authorship Google Reader could define an "archeology" stream -- the best of the past, where 18 months might be the start of old.
Google's probably not going to do this, but a third party service could do this and create a feed. Yahoo!'s wonderful but forgotten Pipes! product could be modified along these lines.