N.T. Wright spoke at Calvin College back in January on the topic of "Space, Time and Sacraments." The audio for each session can be downloaded from here.
Barb linked to these talks back when they came out, but I finally found time to listen. Wish I hadn't waited -- they're really good! I especially like the way that Wright grounds his discussion of the sacraments within the larger framework of creation and new creation, rather than discussing them as an isolated topic. Obviously, the material has far more depth than can be addressed in a day-long seminar, but Wright gives a compelling overview with much food for thought (pun intended).