Magnify any part of your screen with ZoomIt
ZoomIt is a light and free program that will let you magnify any part of your screen. You can have it hidden in the system tray and use it with any shortcut key you like.
When ZoomIt is active it lets you “browse” your enlarged desktop areas and make annotations on them, even using your pen if you prefer to draw.
When you launch the program for the first time it will popup a menu to let you setup a shortcut key you prefer and to inform you on the functions of the program.
Among its functions is a timer that will give you an alert whenever it’s time for a break. Of course you decide when your breaks occur.