I’ll just start with a simple system comprised of User, Newsletter, List and EmailMessage objects, together with a UsertoNewsletter joining table. User will have UserID, FirstName, LastName, EmailAddress, Unsubscribed and Lists. Newsletter will have NewsletterID, Subject, From, PublishedAt, Status, HTML and Text. List will have ListID, Title and ShortDescription. EmailMessage will have To, From, Subject, HTML, Text, UserEmail, UserID, NewsletterID, SentAt and Status.
Screens: List, view, add, edit and delete for User, Newsletter and List along with Publish and Test screens for the newsletter. Not much of a newsletter system, but hopefully just enough of an application to test out the core features of the new interface. I may also throw in a page based content management system as well just to round out the simple test case.