I would really like something like that navi-roller below my spacebars on my keyboard, to use as a way to select from drop-downs and push to enter. Unfortunately keyboard navigation of graphical elements is really lacking these days.
I didn't phrase it very well, sorry about that. I meant that display managers, UI toolkits, and browsers don't support the keyboard as much as I'd like.
But still, adding a mouse-contraption below your keyboard could make it feel like you're using the keyboard to run it while your computer recieves your input as mouse signals, so you'll both be happy.
(Some brand names to search for are Rollermouse, Mousetrapper, Optapad, andErgoslider.)
