Adding membership and role functionality to Silverlight 2.0 is no easy task, but fortunately for us, RIA Services makes it a snap with 3.0, in fact it's practically built-in. This 5 minute screencast shows how to create a Silverlight 3.0 business application with membership and how to assign your own membership and role providers with existing aspnet or membership databases. If you don't already have it, you will need to download the .NET RIA Services SDK Refresh.