Craig McMurtry and Vitorrio Bertocci just came out with a new tool that allows you to examine web services interaction LIVE! I was recently preparing for a presentation on WCF, and a colleague of mine, suggested that I take a look at this tool. Its a great tool, and can be extremely helpful. But thats not all - the coolest part of this is the fact that it uses a Windows Presentation Foundation component to display the interactions of those web services.
Anyways, take a look: http://blogs.msdn.com/craigmcmurtry/archive/2006/09/19/762689.aspx#Purpose