ZDNet: Microsoft is moving to a business model that will depend more on services. But could you envision a future in which Microsoft desktop apps would be free for download -- with the company making its money on associated services and back-end offerings?

Ballmer: People always will be willing to pay for innovative applications that enable them to be more productive and efficient, and that will be a key part of our business model for a long time to come. At the same time, as we move down the .Net path, clearly software as a service and providing back-end technologies are going to become increasingly important.