I live in DC, my commute is 1.5 hrs/day on the Metro. I consider this my time. No internet, no cell phone. I set a goal "theme" for each week, it could be getting a project done, move along an idea, learn something new, whatever.
Each week, I get one full day (~7.5 hrs) of learning/doing something new that would have otherwise been spent watching others play Angry Birds or Sudoku. To date, I've read the notable lean startup/venture finance/start something/be inspired books, listened to all of Andrew Warner's interviews/taken notes, run through all of Rails screencasts, updated my linkedin, launched a small blog, built a couple MVP apps and have hammered out most of the details of a project for an upcoming YC application. Next up is learning more about managerial finance & economics of ventures small and large.