My fiance was watching one of our favorite shows (Top Gear) and there was a little blurb on this company in the U.K. known as ScooterMAN.
What an insane concept to have this company which has been created to act as a safe ride of sorts. A person can go out and about town and call this company, either beforehand or as the night is winding down, to come get them. ScooterMAN arrives on.. yes a scooter, that folds up, they place it in your car and drive you home. Then they get back to work hoping all around town making sure people do not drink and drive.
Check it out! Perhaps there is an application for such a company in the United States such as San Diego or San Francisco to start out. Cabs are not as overpowering as they are in New York and Los Angeles in those two areas and there is a still a pretty heavy nightlife scene. Just some food for thought.