Windows 7 users can change the size of text and icons using the Displaycontrol panel and can zoom in on text using a magnifier tool that can be activated in the Ease of Access control panel, which contains other options for making items on the computer easier to see.
The concept in question is quite simple: a primary LCD would be visible at all times, and when the occasion called for another panel or two, they'd simply slide into view, ready to serve as a number pad, or settings control, predictive textdisplay, or even a full-fledged split keyboard.
As suggested by a newly uncovered Apple patent, you would be able to manipulate and control graphical elements on your display, such as icons, media files, text and images.