Here is a nice magnifier which I have recently heard about. For anyone who requires a screen magnifier for their computer it’s worth a look. It works differently from most magnifiers in that the magnified section is obtained by a two stage process. First the user places the cursor over the target area and then clicks any mouse button. This causes the area around the cursor to be magnified. While magnified, the user controls a standard mouse pointer inside the magnified area to preform click or drag within the magnified space. After the user performs an action, the Pointing Magnifier returns to its original size.
Some other free options for display enhancements can be found at TechDis