One of the cool things about blogging is that it fosters the cross-pollination of ideas. Often, moreover, the derivative idea is much better then its source.
Bob Warfield's post, The Psychology of SaaS and Web 2.0 Persuasion (and Selling), is a great example.
He picked up on my post regarding Cialdini and the psychology of compliance and wrote a very thoughtful piece on how Cialdini's work can be applied to SaaS and Web companies.
It is well worth reading.