Exploring Content Filters
http://www.boxesandarrows.com/archives/exploring_content_filters.php

Evans, Clifton
Boxes and Arrows
2002

Abstract:

What if there was a new way of navigating an online information space we've all seen before but just never thought to use? I'm talking about subtracting away information the user doesn't want. Content filtering is a much more natural way of sorting through categories, especially when the majority of your content is under more than one subject.