Speaking of Communes,

An Anarchist Solution to Global Warming

... Some cities have been abandoned, trees are growing up through their avenues, rivers rush where asphalt had once covered the ground, and skyscrapers crumble while deer forage at their foundations.

Other cities are thriving, but they have changed beyond recognition. Rooftops, vacant lots, and sidewalks have turned into gardens. Fruit- and nut-bearing trees line every block. Roosters welcome every dawn. About a tenth of the streets—the major thoroughfares—remain paved or gravelled, and buses running on biofuels traverse them regularly. ...