I never choose to use a title. Ever. If, on the internet or a form, when it won't let me go any further without choosing one, I use something ridiculous, like Lord or Rt Hon, because it's ridiculous to 'make' me use one. I am always just first name, last name, and at work, with my qualifications afterwards. I think the Germans did a good thing by using Frau for every female, and if we went to Ms for every female here, that would be a good thing. We are very happily unmarried, and I'd never even consider taking DPs surname, should we ever take that step, so I don't see why my nomenclature should have to reflect that.
Rant over - more wine! :)