Trek make something like this
http://www.trekbike.co.uk/bikes/city...uiser/7400.php
but its only on their UK website. I saw one locked outside the railway station a few weeks ago, and thought it was some custom build by an experienced commuter.
Brixton Cycles, a commuter shop in London also made a quality 7speed for urban riding . Its a very sound concept, and I wonder why it has taken so long for the manufacturers to twig.