Windows: The Windows built-in magnifier tool was designed more for aiding those with vision problems than aiding those giving presentations. AeroZoom is a supercharged magnifier that makes it effortless to zoom and adjust your presentation view with simple mouse clicks.
AeroZoom is a portable application designed to take components of Windows such as the Magnifier and the Snipping Tool and make them more functional for presentation purposes. Instead of fumbling with the keyboard to perform what should be mouse-friendly actions — there is no scroll wheel-based zooming in the default magnifier for example — AeroZoom packs everything into the mouse so you can comfortably zoom and adjust your presentation without squinting at your keyboard.
Check out the video above to see it in action or visit the site below to read more. AeroZoom is freeware, portable — the author has thoughtfully included two versions of AeroZoom in the small download, one for both right and left-handed people — and Windows only.