I'm currently watching the Nova episode on the great Gothic cathedrals. I am also reading a book on the medieval city, which has a chapter on the cathedrals, so this is really fun! It is so amazing both what they knew and yet what they didn't. It just amazes me what they managed to build without modern tools! Just cool! Definitely worth watching (or reading!).
I also watched Presidential Prophecies (my review is the link). Not as good, but kind of fun.