ZoomIt is a free utility for Microsoft PowerPoint presentations that helps you to screen zoom and make annotations technical presentations that include application demonstrations.
ZoomIt runs unobtrusively in the tray and activates with customizable hotkeys to zoom in on an area of the screen, move around while zoomed, and draw on the zoomed image. The application let you run demonstration and apply zoom in and zoom out.
Once you install ZoomIt, the first time it will presents a configuration dialog that describes ZoomIt’s behavior. This dialog let you specify alternate hotkeys for zooming and for entering drawing mode without zooming, and customize the drawing pen color and size. You can change the hotkeys to match your desired configuration.
ZoomIt also includes a break timer feature that remains active even when you tab away from the timer window and allows you to return to the timer window by clicking on the ZoomIt tray icon.
Go to download ZoomIt http://technet.microsoft.com/en-us/sysinternals/bb897434