I would love to see a public transportation option to offer people a quick and easy way to get into and around the downtown core, as well as provide reverse commuters with a way to get from the train station to offices just beyond what most people would be willing to walk on a daily basis.
Providing a hop on / hop off shuttle for "the last mile" would help to cut back on traffic, make commercial space just out of walking distance to the train station more appealing to businesses and their employees for reverse commuting, allow visitors to see what all the area has to offer (instead of paying attention to traffic) and provide a fun way to get around downtown on the weekends. 
Ideally, I would picture a shuttle with a historic look (but maybe electric engine?).
For more information on this concept, see this NPR piece from 2013 about Emeryville, CA:

Posted in: All Placemaking Ideas, Mobility