Ethical, environmentally-friendly bike manufacturer

Bicycles are great for the planet - getting people out of cars and requiring little more than bananas, flapjacks and the odd bit of oil to run. But most bike manufacturers aren't taking the environment into account much in manufacture.
Racer Rosa Bicycles make made-to-measure handbuilt bikes. The frames are made in Italy from Italian steel and shipped to the UK, then assembled with components picked for ethical/environmental benefits as well as quality, all in Walthamstow, East London. Want to know more? I wrote them up for The Guardian's Environment site.