Out here in suburban sprawled California, distances to the main train station tend to be between from between 2 and 10 miles, for those who would be using rail on a daily basis.
In fact, because the station is in the center of the original downtown and there's been a lack of interest in restoring the city center, there's actually a two-mile "Dead Zone" around the station, a zone in which very few potential riders reside.
That's on the departure end of things for my town. People are going to have to learn to use the bus system or use cars for the foreseeable future, they aren't going to walk 3 or 4 miles or more twice a day. Some might bike some distance, however.
I love the bike locker idea, that serves some number of riders. Also, buses and the train allow riders to bring their bikes with them, no charge.
On the destination end, in places like San Jose, Fremont, Livermore, and other work or shopping destinations, we are looking at Zip Cars, rented bikes, electric bikes, Trikkes, and even Segways.
Electric Bikes, Trikkes, and Seqways have the advantage of not requiring special licenses.
With any of these, however, there needs to be a form of security and coverage for loss, so a small rental fee or government subsidization, and some type of credit card backup to track who's been using which device, these are all being considered.
Thanks again.