In 1962, a fire began in the garbage dump of Centralia, PA. It ignited an exposed coal vein, and since the town lacked the resources to adequately handle the situation, the fire spread to a series of abandoned mines beneath the town, igniting more coal. In the 80s, it was ruled that the town was too dangerous to live in, due to sinkholes and poisonous gas, so the federal government seized the land by eminent domain and appropriated $42 million to compensate residents for their homes. But some people refused to leave. In the 90s, dozens of people remained in Centralia. Now there are only five remaining houses, down from sixteen in 2006.
It's a fascinating story:
http://news.yahoo.com/s/ap/20100205/ap_on_re_us/us_centralia_s_final_days