I realy like some of what Plymouth State is doing to allow browsing by LC subject. If you click, for examle, Sociology, you are taken to a sort of socioloy portal that contains links to course guidelines, relevant databases, pre-populated searches of the OPAC, reference materials, websites, and the sociology librarian's contact info. Click on a pre-populated OPAC search and you are able to broaden/narrow the search by clicking tags as well as bookmark or choose from RSS options.
LibGuides - Knowledge Sharing for Libraries
LibMarks - Social Bookmarking and Tagging for Libraries
Came across these SpringShare tools today - LibGuide (for subject guides) and LibMarks (social bookmarking for libraries)...
Darthmouth uses LibGuides for their subject guides. http://libguides.dartmouth.edu/ . Looks really cool!