Daniel Phillips and Kim Karlsrud are the designers of Greenaid, a candy machine for seed bombs. Seed bombs are packed with clay, compost and seeds. They're tools in a growing guerrilla gardening movement, which encourages people to grow flowers in abandoned lots and other barren locations. Danny and Kim hope people throw the "bombs" in an abandoned area and watch the flowers grow.
This map lists the location of Greenaid's candy machines selling seed bombs:
View Greenaid Vending Machine Locations in a larger map
There are other maps on their website with lists of potential seed bomb locations and where they've already been thrown.