What a great idea: LA-based design studio Common Studio has been taking regular ole' candy dispensers and using them to share seed bomb packets. The Greenaid project dispensers, described as an "interactive public awareness campaign, a lucrative fundraising tool, and a beacon for small scale grass roots action," are available to purchase and dispense seed packets suited to the unique ecology of your area.
Their test model was placed in Los Angeles's Chinatown and filled with indigenous plants. Right now machines cost $500 to retrofit, but if they can partner with botanical gardens and parks, they're hoping to drop that price. From the Common Studio Web site, here is a description of their project:
Made from a mixture of clay, compost, and seeds, "seedbombs" are becoming an increasingly popular means combating the many forgotten grey spaces we encounter everyday-from sidewalk cracks to vacant lots and parking medians. They can be thrown anonymously into these derelict urban sites to temporarily reclaim and transform them into places worth looking at and caring for. The Greenaid dispensary simply makes these guerilla gardening efforts more accessible to all by appropriating the existing distribution system of the quarter operated candy machine.
They've also put together a great video describing their cause: