For many of us, the Windows Magnifier tool is something we've occasionally activated by accident. There's a lot more to Magnifier in Windows 7 then just a big box that shows pixellated mouse movement, however. It makes for a great laptop-in-bed helper, for example.
The Online Tech Tips blog runs option by option through the Windows 7 Magnifier, which has three modes: a docked, screen-width view, an adjustable box, and, most helpfully, a magnifier of the entire screen. That can come in handy when reading a laptop screen from a bit farther away, as when giving a presentation or doing some browsing in bed. A small control box makes it easy to turn the Magnifier on or off, as opposed to hunting down the keyboard shortcut. Get a feel for how Magnifier might help you out at the full post.
Use All the Features of Windows 7 Magnifier Program [Online Tech Tips]