Only I saw in the paper yesterday that health minister Ann Keen was the first MP to be found to have breached her duty of care to a constituent last year - had to pay £15k damages for failing to assist someone.
So, if your MP can't be bothered to listen to you, there is a way to make them sit up and pay attention...
(It was in the Mail, btw, I know this is A Bad Thing on MN but useful info nonetheless - p7 story headlined 'Mr and Mrs Expenses' as Keen and her hubby both claim second home allowances despite living in London.)