The only real tool for developing cross-platform Rich Internet Applications (RIAs) for that last 11 years has been Flash; until now! Silverlight 2 allows you to develop cross-platform Rich Internet Applications in a fraction of the time because of the extensive and very powerful .NET 3.5 libraries, the powerful, design friendly Blend 3 Integrated Development Environment, and an enhanced workflow that allows designers and developers to work on the same set of files at the same time.