TWO POWER SUPPLIES
Ain't that easy? I can leave one plugged in at work to the docking station (and don't have to get under the desk to unplug it every day), and leave the other one (smaller) at home, or use it to travel.
Most of the time I won't need to carry any power supply at all, since the 3.5 hr battery life is enough for my mobile days...
To me is the greatest simple idea in a long time of carrying hardware around on my shoulder. Kudos to the ingenious fellow who thought of it.