I am an avid cyclist (I don't own a car, and the bicycle is my primary mode of transportation), and am also a photographer. When I have mixed the two in the past, it has been with a 35mm rangefinder camera which is easy to carry. However, the primary film format that I shoot is LF, which is less pocketable. I am wondering if anybody else on this list carrys a LF kit around on a bicycle. My usual LF kit is loaded in a backpack (Kata Panda-402), and I am thinking of getting a Burley Travoy trailer to haul the camera and a sturdy tripod with me on the bike. I have concerns in that the Travoy has small wheels, so it is probably more bouncy than other solutions, but I do like it's compact nature.
Don't know if this is helpful, but a guy rides around town with one of these - very cool! The FreeRadical is an add-on to a standard frame:
Just a few months ago, Bicycling magazine had a good article on the bike as major transportation and offered some unique ideas for what you are looking for, like going to the grocery store etc. Hope that helps.