If you like category theory, the lectures by The Catsters on YouTube at http://www.youtube.com/user/TheCatsters http://www.youtube.com/user/TheCatsters are ente

If you like category theory, the lectures by The Catsters on YouTube at http://www.youtube.com/user/TheCatsters http://www.youtube.com/user/TheCatsters are entertaining. Their latest video describes Lawvere's example of generalized metric spaces as categories enriched over the set of nonnegative real numbers interpreted as a monoidal category.