It would be very useful to use a hard button on the PPC to 'toggle' a boolean device property like "PowerState". To be able to click a hard button to turn on the light if off and turn off a light if on would be nice. I know that since they aren't really 'typed' values, this may be a hard model to incorperate in practice. To specify it would be easy entering"New Value" of "+-" for a "Panel:Buttons" item. Perhaps it could work similar to the "Multistate Button"?
Right now I need to use two of the limited hard buttons; one for off and one for on. Maybe it can already be done but I haven't learned how yet?