Everyone who has ever created a webservice in PHP, using the PHP5 native functions, NuSOAP, PEAR, ..., certainly has cursed a lot while creating WSDL files for those services. Today, I found a nice helper class, Webservice Helper, which does a lot of tricks for you.
Webservice helper creates the WSDL file for your service, and for related classes. Also, a basic authentication system is included.
One necessary thing in your code is PHPdoc-style documentation. Webservice helper travels that documentation and uses reflection to generate class mappings. But normally, one should always document code.
As I'm a C# fanatic too, I created a simple service using Webservice helper, and tried connecting using C#. It works perfectly! The web service browser in Visual Studio recognizes the WSDL and generated method names, and talking to a PHP webservice feels just the same as talking to a C# webservice. Maybe I should think about enabling some webservices on my blog to allow me to easily post new articles...