Oren has a great post on mocking WCF (client and service) using Rhino Mocks and Castle Windsor (sneaks some Boo configuration in there too :) as part of a real world Test Driven Development example.
A quote from one of the comments:
"I call this the prevailing WCF real-world blog post on the internet right now. Do you sleep?" - Jay R. Wren
Oren claims to sleep in a follow up comment but if he does that just means he is coding with his eyes closed.