Way back before we thought of publishing a book, we created a booklet of case studies. Although many of the case studies have been republished in the book, you will still find some of these interesting.
I haven't managed to make each one a separate page on this website so I've uploaded the whole book. I hope it is useful
http://www.b12d.org/book/casestudies (you reach it by clicking on the "Obtain Book" and selecting from the drop-down)