Using WCF as a service bus to pass data

I have heard of the idea of using WCF as a "bus" between tiers in an nTier project to retrieve information (lets say a set of product prices for example), which comes from the business tier, and then the data that bus retrieves is shown in the presentation tier. I did some interview questions on a system based on the same foundational concepts.Does anyone here have any links of how this is done with WCF and C#?Thanks ...