One thing that's keeping my hand on the mouse and stopping me from going full keyboard, is the free scrolling mousewheel on logitech mice. I find it such an ergonomic and natural way to get to the right place in long documents (and code).

What I would really love is a keyboard with this sort of scroll wheel embedded just on the edge of the keys. All the keyboards I see with knobs / rotary encoders look cool but I can't see myself using a vertical knob for scrolling a document. Do any custom keyboard builds feature a mousewheel?