We went recently for a visit to a local eco village and saw some permaculture gardens and came back inspired to switch ours around (again) They had quite a few compost heaps, and lots of interesting ideas, like climbing frames for plants and companion planting
Ever thought about generating your own electricity ? Growing your own food, living sustainably ? Maybe keep a chicken or two and some animals ? Living off the grid may not be for everyone but for enthusiasts its the bees knees and you don't need to go totally off grid to become a part time urban farmer.