I have been using a very simple and very useful habit tracker called Joe’s Goals. It is a very powerful tool that gives a visual display of how well one is doing in learning new habits.
I think there is further scope for applications like this, particularly in Outlook – but I am unable to find any that really work.
In any time management system, it is critically important to find effective ways to unlearn and learn new habits, and having an effective display of progress is only a part of the battle, but an important one.