Smarter News Aggregation

When I click a link in my RSS reader that links to a post on another site I subscribe to, it should be smart enough to re-direct me to the post in my reader instead of taking me to the site. I'm not sure what it would take to engineer this, but it would sure save some duplication of effort on my part and it wouldn't require an unnecessary http request. Nick, Greg, are you listening? Is this possible?