Soma has small reach brake levers for road bikes. (They are actually made by Tektro). Because there is no shifter mechanism, the whole thing can be smaller. You'd have to put bar end shifters or downtube shifters on, though.

http://www.somafab.com/aerolevers.html


Someone correct me if I'm wrong, but I think Bianchi uses Campy. Campagnolo are smaller than Shimano.