The Asp.Net membership provider has some clear uses in a web app. I am thinking about trying to leverage some of the features in a windows application (more specifically WP
Make sure that you are creating a 3.5 application (WPF 4 won't work yet) - Then you must import the reference System.Web. This will allow you to use "using System.Web.Security;" like you normally would in a web app... now you can access stuff such as Membership.CreateUser()
Your app.config file has to be configured for your provider along with a connection string.