You can use them with one hand and I've thought about trying them so that I could use the mouse with one hand and the keyboard with the other instead of having to switch back and forth, but they're not friendly to hunt-and-peck usage, so most people probably will never learn to use one.
http://en.wikipedia.org/wiki/Chorded_keyboard
You can use them with one hand and I've thought about trying them so that I could use the mouse with one hand and the keyboard with the other instead of having to switch back and forth, but they're not friendly to hunt-and-peck usage, so most people probably will never learn to use one.