This NY Times article gives a good overview how urban dwellers can compost in tight spaces. While I think many people feel in high density areas composting is not possible, this overview of the vermicomposting process demonstrates how composting can be as easy as recycling.
The workshop covered the indoor composting method known as vermicomposting, in which worms are enlisted to speed up the decomposition of organic material, eating through scraps of it and excreting the “castings” that make up compost. (There are also commercial composters like the NatureMill, shown in the article below.) The “condo” where this should take place is a 16 1/2-inch-wide, one-foot-tall bin with air holes in which shredded newspaper sits atop green trash like the ends of carrots. Despite the enthusiasm of the audience, particularly the children, as containers of compost and worms were passed around, some of its members seemed to have misgivings. “Will the compost bin attract roaches?” one asked. (Not if you don’t let the covered bin get smelly, he was told.) “What happens when you go on vacation?” (The bin can stay unattended for up to three weeks.)
This article really helps to demonstrate what people can do on an individual level, but that will have a larger effect on our environment. While technology is helping us be better neighbors, composting, rain gardens, water barrels, and recycling are all steps we can take on a smaller scale, that will eventually pay off down the road.