Smart client technology
What is smart client technology? Microsoft is extensively marketing smart client technology as part of its .NET initiative. This excerpt from a Microsoft article defines smart client benefits:

“Key capabilities now exist which mean that we can take full advantage of the rich client model, providing the user with an excellent user experience, while at the same time reaping the benefits of centralized deployment and update. In short, this new generation of client applications, the so-called "smart" clients, provides the best of both worlds and adds the intelligence to manage data and connectivity to produce an extremely compelling user experience.

As the above diagram shows, while smart clients provide the benefits of a rich client model with thin client manageability, they also provide much more flexibility than the traditional rich client applications. For example, smart clients need not be designed as monolithic desktop applications. Smart client solutions can be developed that are composed of functionality from more than one client application, with each application collaborating with the others to provide just the right functionality to the user. Such "composite" applications integrate client-side software resources into a coherent solution, or extend the functionality of an existing application to provide smart client features.”

For more information on .NET smart client technology, try the MSDN Smart Client Developer Center that in turn provides numerous links to useful smart client resources. If you are primarily interested in more in-depth understanding the business value of smart clients, try the Microsoft Smart Client site.