Margaret sends this link to a photo essay about the trash collectors of Cairo.
The Zabaleen, or "Garbage People" in Arabic, are a sort of lower caste who perform the vital task of removing much of the city's detritus. Until the 1980s Cairo had no official garbage collection, and even today up to half of the city's waste is collected and sorted by the Zabaleen. Since they are Coptic Christians, they are allowed to keep pigs to eat the organic parts of the garbage, while recyclables are collected and turned in for a meager income.
Many of the garbage collectors live the slum neighborhood of Manshiet Nasser, where women and children sort garbage in their homes, brought back by men with donkey carts scouring the city. The neighborhood was in the news in September 2008 when a landslide from a nearby cliff destroyed numerous simple houses and killed some 50 inhabitants.