Alleys - a neighbourhood mechanism

A traditional hutong in Beijing. Image courtesy flickr user tsc_traveler.

Melbourne - where I live - is well-known for its alleys and the creative uses that they have been put to. This is a great approach from a non-profit in the USA (read more here):

Most alleys had simple utilitarian origins as ways to access buildings with goods and vehicles — especially where a socially decorous street frontage was desired. Commercial blocks in older American cities are often bisected by alleys. In Los Angeles, many retail streets have alleys for service and parking immediately behind the stores, with larger residential blocks behind. Residential alleys serve townhouse districts in Boston’s Back Bay and much of Washington, D.C., (but not New York). In Venice Beach, alleys make canals and “walk-streets” possible.Beijing’s hutong and Shanghai’s longtang alleys are the basis of the traditional residential fabric. These narrow lanes host a rich mixture of local functions, including access to the modular courtyard houses they serve. The explosive growth of Chinese cities has made these districts and their way of life something of an endangered species despite belated efforts at preservation.