I was focusing on personal use at first but obviously business and academia uses make sense too, especially in our milieu. My summit presentation is being created in Microsoft Powerpoint but using that to present the slidshow at an open source conference violates the spirit. I don't expect Microsoft to provide such a tool, but here's where a third party translator would be handy that could refactor the PPT into an XML-based format for sharing/presenting to non or anti-Microsoft audiences.