Google Reader Idea: Filter Feeds

I follow dozens of different websites through the use of RSS feeds in Google Reader and each day I can read anywhere from 50-600 posts(some posts are 1-2 sentences). I am also very organized so I keep my RSS feeds separated into folders in Google Reader. I have folders for "Must Read" items as my daily news, "Video Podcasts" as my tv shows, "Android" folder for all of my Android related news etc. Well this gets complicated because sometimes I get news about Android from New York times or Wired which shows up in my "Must Read" items, when I would prefer if they showed up in my "Android" folder. My idea would to be to follow all of the feeds like normal, but then be able to create filters like in Gmail where I can have all posts related to a filtered topic go into a special folder. ie. ALL Android posts showing up in my Android folder. This would make it possible to create a web based magazine(sort of) from topics that you like to read. By creating filters, users would be able to follow new RSS feeds that cover many topics and sort them into more useful feeds. Also by giving users the power of creating custom filters we can "mark items as read" that we don't find interesting. Do you think this would be useful?