Well Documented Open Source Business Case?

PeteQC asks: "I'm currently working on a project and I need solid and well documented case studies about actual implementation of open source in an enterprise (failure or success). My goal is to use the grounded theory to build a scientific model on Open Source adoption. I've searched through the web, but the only good case I found was the Beaumont Hospital Case. (Which was also published in IEEE Software, January/February edition). I'd like to know if Slashdot knows of other well-documented case studies which I may use? I'm looking for a link to a web site or a reference to a specialized publication, but all assistance will be welcomed."