Sacramento is fairly walk-able and has a very robust public transportation system. I took it the entire time that I was in town and never felt that I needed a cab or car. I was also very impressed with how easy it was to purchase a fare pass. Some public transport systems make it impossible to get around without using cash or tracking down an information booth in a random part of the city to buy a pass. Sacramento uses an app called RideSacRT which allows you to purchase a single ride fare or a daily pass directly on your smart phone.
Not only is this super convenient, it also works on both trains and buses. This makes getting around Sacramento without a car as simple as possible. It seems that most public transport systems outside of huge cities are geared toward locals and commuters, I think that the Sacramento Regional Transit system was by far the easiest one to understand, navigate and pay for from a tourists perspective. I hope more cities adapt these types of technologies and take a lesson from Sacramento when it comes to lowering the barrier of taking advantage of public transportation.