I highly recommend Unqualified Reservations ( http://unqualified-reservations.blogspot.com/ ) and Unenumerated ( http://unenumerated.blogspot.com/ )

Both are incredibly smart blogs, with very smart commenters. Their main shtick is bringing historical perspective to contemporary problems of government and economics. The result is fascinating and eye opening. I've learned more history from these two blogs then I learned from majoring in history at Yale.