I like to use Google Reader to keep track of interesting blogs and news sources. Usually when an article is linked from HN I take a look at the site and see if it's interesting, then check if it has an RSS feed.
Good point. I do this too, though it takes regular pruning of the RSS feed list to keep it interesting. I'll usually sign up for a feed from a blog or site that seems interesting, and after a few weeks or every few months check how often I actually read that feed. If not, out it goes.
Indeed, pruning the feed list is important. I usually only remove a feed if it keeps annoying me with frequent irrelevant content. What I want to prevent is having too many unread items in my reader because it leads to either wasting too much time filtering through them or deciding it's not worth the hassle and missing out on good articles.
