It's no secret to people that know me that the thing I want most in the whole wide world is a Christiania bike. This is a Christiania bike:

You can transport a lot of stuff in these things! In Copenhagen you see a lot of these bikes, mostly with kids in the front peering out of plastic covers. Unfortunately, my dream of being the first christiania bike-rider in Cambridge was shattered a couple of days ago when I spotted one on midsummer common. These bikes are expensive, the basic one costs about £1000 and there are only one or two places that you can buy them in the country so there's little chance of finding one second-hand. I think they're gaining popularity though - I've seen a few in London now.