Jason Fried on teaching to get more business

The 37signals blog pointed me to a video talk by Jason Fried (founder and CEO of 37signals) where he talks about how businesses can use teaching as a way attract and retain customers. To paraphrase the 14 minute talk, telling your customers how and why you do what you do can actually make you money. He talks about how 37signals repurposed a collection of their "lessons" (describing the strengths of their own application development "philosophy") from their blog into a book and a conference... both of which made them money.