We have just changed our organic deliverist on recomendation from The Observer a while back and a very good system it is too. Rather than just getting given what you get, you can remove items and swap for something else. I was getting rather fed up with recieving boring broccoli, I didn`t mind the purple sprouting variety in the spring, which is really nice, but I found that just putting a green thing which nobody eats , on a plate, was pointless.
Anyways, you Londoners can get this one as well.

www.abel-cole.co.uk

I love food shopping online, you can gradually build it up all day whilst leaving the list open, much better than the old hand written shopping list that you neglect to put in your back pocket.