This is the rather grand title of a WebCast I've recorded recently which tries to illustrate where the return on investment comes after moving to a SOA strategy. The video is on Digital Forum: Visualizing SOA ROI , and the Open Source proof of concept it references is on CodePlex: ESBSimpleSamples.
In the WebCast I start with a blank Visual Studio solution and create a new Web app which consumes an existing service. All in it takes 3 lines of code and around 3 minutes of development (most of it spent correcting typos), and it doesn't require me to have any understanding of the underlying SOA infrastructure – in this case, Microsoft's ESB Guidance package sitting on BizTalk Server 2006 R2. Equally important, assuming the service we consume is in production, the testing and deployment effort needed for the new project is minimal.
This is a rework of a presentation I did with a client where I wanted to show how quick and easy it is to use their SOA implementation. I had reservations of showing a code demonstration to an audience which included IT heads (IT Director and Solution Architects) and project management, but it was surprisingly well received, so I've reproduced it using services and components which are publicly available.
Direct links to the references in the WebCast are here: