The day after 9/11, a man appeared at a New York City firehouse offering to help. He was a former employee — he had worked at the firehouse from 1980 to 1984 before changing careers. Despite his nearly two decades away from the firehouse, though, he was still a familiar face — he was actor Steve Buscemi. According to Wikipedia. Buscemi spent the rest of the week doing 12-hour shifts looking for lost firefighters and other victims of the attack.
Source: NoW I Know That’s Half the Battle by Dan Lewis