I'm in the process of constructing the best commuting bike (atleast according to me). Surly LHT, with a wheelset comprising of Mavic A719's, xt hubs, and double butted spokes, some sort of handlebar and stem from nashbar, chris king headset, aero bars with bar end shifters (incase theres a long car-free stretch of road), and some fenders, racks, cantilever brakes, gears ect, the type of which I have not decided yet.
In my mind the ideal commuter....