I, for one, have never been happier that my MP is a Conservative.
Not that I've heard back from him yet, but theyworkforyou.com shows him as responding to 'a very high' number of communications via writetothem.com - something like 84%.
Of course, I'm registered to vote in one constituency and living in another (university student)... that might just give me two possible avenues of approach anyway. May have to look into this. Just a shame that the Nottingham MP is labour and never rebels against the party line