This delightful video shows how a family in East London is keeping chickens happily in their yard, http://www.guardian.co.uk/environment/video/2010/jan/01/ask-lucy-chicken-green-living.
The three include a Leghorn, a Polish and an undetermined dark-feathered variety. Perhaps a Cuckoo Marans, since her owner says she lays dark brown eggs. The Leghorn, bless her, continues to lay through the winter. This Leghorn and her eggs are from Purity Feed in British Columbia, http://www.purityfeed.com/orderchicks.asp.
Although the owner's plan is to eventually kill and eat them when their laying declines, I couldn't help but note that although they are already past that, he hasn't gotten around to it yet. This is a dilemma for backyard chicken keepers. If you are committed to efficiency and economy, then feeding chickens who lay few eggs doesn't fit that plan. However, people and chickens being what they are, people generally become emotionally attached to their birds when they keep only a few. So dispatching them and eating them becomes unacceptable.
Some small farmers who keep chickens as egg producers have resolved the issue by giving more weight to the value of the eggs produced during those productive years, balancing the future less-productive years. They commit to the chickens for their lives and keep them on regardless of how many eggs they produce.