Joe Ely's Learning About Lean blog is interesting because for me, its content is an unusual mix of relevant and irrelevant. Joe is the directory of quality for a building company, and his blog is about Lean Manufacturing, which seems to be a movement about ultra-efficient manufacturing processes, at least in terms of supply chain dynamics, inventory, and so on. I really don't know anything about it.
But that's part of the interest: he talks about improving processes for a domain that is completely foreign to me, but it is all relevant to my work anyway. Depending on your appetite and capacity for business-speak about improving work habits, processes, and project techniques, you may find it interesting as well.