New York City showed signs of getting back on its feet on Thursday in the aftermath of the devastating Hurricane Sandy as its 108-year-old subway system roared back to partial life at 5 a.m. Thursday morning. "It's the lifeline of the city," said one early rider, Ronnie Abraham. The subway will only offer limited service, as much of downtown Manhattan still has no power and only three of the eight East River subway tunnels have been dried out. In areas without subway service, there are some shuttle buses running as well as regular bus service. All subways and buses will be free on Thursday.