A couple weeks back Brad Abrams came to speak to the Triangle .NET Users Group (TriNUG). During his presentation he used and breifly mentioned ZoomIt, a utility for zooming in to sections of your screen.
I downloaded it and I've got to say ZoomIt is great. I think it was a 3rd party utility at one point but now it's a free Microsoft download. If you've got a presentation in your future, it's a must have.