what might be useful is a footboard for the modifiers (alt, control, shift, win, plus maybe backspace). That way you keep your fingers on home row even more of the time. And exercise your legs a bit.
lowpoly, want to rig one of those up?

if there's room for more buttons (and if it makes ergonomic sense), then also foot pedals for controlling the music player (play/pause, for/back, volume/mute, and skype answer).
Wire in an ac adapter down there as part of the footboard, and you have foot-controlled switches to turn on/off your speakers and printer.