One of the blog's readers from Italy, Fabio Cozzolino has written a interesting host for WCF that gets and merges configuration from different configuration files. You can download the code from his post, which is completely in Italian. (Anyway, the code is not, it is English).
Many times the services are just part of a service layer interface or facade that only delegate calls to other components in lower layers, such as entity translators, business logic components, data access components or service agents that work as proxy with other systems. To clarify more this point, this is how the Patterns & Practices team envisioned a general multi-layer architecture for .NET applications, http://blogs.msdn.com/donsmith/archive/2006/07/21/673481.aspx