There are three Community Chest squares on the board, and 16 possibilities for what you might pick up. Most of these don't have a meaningful cycling equivalent, such as doctor's fees (hopefully not, anyway) or bank errors in your favour. Some can be considered bike-related though. For our first Community Chest card, we've chosen Pay your insurance premium £50.
Insuring your bike against theft is a complex issue. For me, I think the sums involved, and the complicated conditions, exceptions and excesses, don't make it worth insuring a bike in London: better to have a cheapish-but-decent bike; two heavy-duty locks; and accept that you rent bikes for a few years, not own them.
But on the other hand... your Community Chest insurance premium of £50 would get you a year's insurance for a £450 bike through Cycleguard, covering against theft, loss and damage, with no excess.
Membership of cycle organisations such as the London Cycle Campaign or the CTC gives you third-party insurance. Of course this offers no protection against one common situation: namely, dimwit drivers complaining to you in pubs that we don't have to have insurance, and how if only we were licensed it would end this mass slaughter of pedestrians from pavement cyclists. Personally I'm more worried about the 1 in 5 young car drivers who drive around uninsured. Maybe I should copy the anti-cyclist brigade, and write a letter in green ink on the subject to a local newspaper.