I've used a presentation tool for some time called ZoomIt, which I have downloaded on my flashdrive. This free download from Microsoft’s Windows Sysinternals includes a screen zoom, an annotation tool and a countdown clock. Many of these features are similar to parts of other software for interactive whiteboards, but ZoomIt's portability, simplicity and ease of use separates it from the others. The program will run on any PC and hide in the tray after you launch it. If you think this tool could help focus or emphasize parts of your lesson or presentation I’d suggest you download it and give it a try. Check out the short video beneath to witness the power of the zoom.