Although Wichita Falls, TX isn't exactly the town a person would visualize upon hearing the word "urban," an article I found, "Farming the Concrete Jungle, Feeding a Green Economy" is applicable nonetheless.
Some months back a few of us were talking about a use for some properties on the east side of town in the flood plain. One idea for a productive use was to offer the ground as community garden space. This could be of benefit to many people, especially those at lower incomes and inadequate transportation (there aren't any grocery stores in that area of town.) I brought it up at a Park Board meeting, but it didn't seem to get any traction there and to be honest, at the time I didn't need another project. Still don't, but the article reminded me of the possibility. This would be a great project for the Master Gardeners to get involved with (I can suggest it--I am not part of this group.)
2009 also saw the first attempt that I am aware of for Community Supported Agriculture. I heard there were some hiccups this first year, but the point is, there is movement.
Locally grown food is one way to encourage a more sustainable lifestyle.