Web Services Day 4

Today is day 4-of-5 of my Developmentor .NET Web Services Class.  Dan Sullivan is teaching the class to a small group of Microsoft field developers.  The course and instructor are simply awsome.  I'm strangly sad that tomorrow is the last day.  I've learned enough cool stuff in the first four days that I could easily spend months experimenting and playing.  For instance, today I experimented with UDDI, with adding custom SOAP headers,  and with writing a SOAP extension.  Tomorrow we will cover WS-Security and WSE.