I somehow developed a double chin while in France. Probably due to the fact that ate nothing unless it was made in a boulangerie (French for bakery) . . . . mmmmm, bakery.
The entire time in France I did not see one person wearing one, just stoopid tourists like me trying them on.
We spent the first day in Paris walking around and by the end of the day I was shattered. I compare it to Christmas shopping - walk, stop, walk, stop . . . . killed my back. Paris, being a bike friendly city, we decided to cycle around seeing the sights. We didn't have to search around for a bike shop because the city has bike stations everywhere. It takes a few minutes to set up an account using your credit card at a kiosk which is beside the bikes, then you're ready to go. It worked out to be one Euro (about $1.60 CDN$) a day to rent a bike - cheap as chips!
One time we had trouble putting a bike back in it's lock ( a little green light comes on to let you know it accepted the bike - turned red instead). At each kiosk there is a intercom where you can call a central bike station dispatch and they were able to help us through a computerized system. Simple again.
Bike lanes everywhere. Where there were no marked bikes lanes, cars gave cyclist a ton of leeway to ride. I wouldn't call French drivers "aggressive", but rather 'confident and assertive', they still have a tremendous amount of respect for cyclist. North American drivers please take note! Cyclists too were assertive, they didn't flinch in traffic and stuck to their lanes and would often jump out in traffic whenever they needed to make a lane change with confidence.