This fellow, Cliff Atkinson, runs a company called SociableMedia that specializes in marketing and communication around effective use of PowerPoint (no doubt the most maligned communication tool since the stick-in-the-eye.) Clif has a blog with some VERY useful content. Subscribed. Here's some of his articles on PowerPoint and effective communication.
Additionally, here are the ToastMaster's Top 10 Tips for Effective Public Speaking and a pointer to my "Scott Hanselman's Tips for a Successful [Technology] Presentation".
Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. I am a failed stand-up comic, a cornrower, and a book author.
Disclaimer: The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.