Our talented and tireless artist, Brooke Budner, and her business partner Caitlyn Galloway, run a project called Little City Gardens.  Check  their website/blog.
What is Little City Gardens?
It is a small urban farm in San Francisco, and it is an experiment in the economic viability of small-scale urban market-gardening.

We have been working steadily for a year towards our aims: to craft a way for urban food production to sustain us economically, to build community through innovative, collaborative local food systems, and thus to help establish the path of ‘urban farmer’ as a career. We are motivated by the belief that urban farming should be a common livelihood in the United States as it has been, and still is, in some other countries. Through this project we are actively wondering: what does it take to make this happen?
How did the project get started?
Brooke discovered the first garden site in 2007 while scanning the neighborhood from the vantage point of her roof. She contacted the landlord who agreed to let her begin gardening. With the help of friends and neighbors, she began transforming the lot from an unused field of weeds and brambles to an abundant garden. In early 2008, Brooke and Caitlyn met and began working together, sharing ideas and time in the garden. Together they developed vision, community involvement, a name, and a business plan.
What is happening now?
Little City Gardens is currently a small salad greens business, an educational site, and a working model of food production in San Francisco. We provide greens, herbs, and a specialty salad mix for one restaurant and a handful of caterers. We offer tours and host workshops in the garden, and we are currently beginning the process of expanding our operation to a larger site in the city.
What motivates you?
We are young farmers in a nation with a food system gravely out of balance. We know that the economics and politics of food are skewed in favor of large corporate agriculture. This not only creates harsh economic realities for small-scale farms, both urban and rural, but also is fueled by the use of petrochemicals and gasoline, and is based on manipulative global trade policies. We are inspired to get creative. We are working toward an urban farming model that makes up for its small scale by recycling urban resources (neighborhood composting), eliminating transporation costs (deliveries by foot and by bicycle), creating active, face-to-face relationships with neighbors and customers, and enlivening new forms of community support. The more community we can build around the growing of our food, the more power we can have to change our food systems.