clausy, I hear you, but:

1) I can't actually ride a bike. I've signed up for lessons from the council though!

2) I work in Paddington. Forest Hill to Paddington doesn't seem like all that terrific a bike commute...

3) I'm four stones overweight and pretty unfit - though I suspect that if I could get past 1 and 2, 3 would disappear pretty quickly!