If you take public transit that is subjct to delays consider running to work (for distances of 5 or fewer miles). Public transit can be subject to delays so running winds up being more time competive than it seems. For example my train ride is 15-20 minutes but is rarely subject to delays which can bring the trip to up to 30 minutes. So I need to allow 30 minutes for my public transit commute. Since I can run to work in 30 minutes the run fits my morning routine in no more time than I need to allow for public transit despite being slower in the modal case.