Philadelphia Passenger Lists, 1800-1945 (Online at Ancestry)
I saw over at Legacy News that the Philadelphia Passenger Lists from 1800-1945 are now online and easily accessed at Ancestry.com. These are passenger lists from the National Archives and Records Administration. A fairly significant genealogy resource if you are having trouble finding where your ancestors came in at, and the usual suspects don’t turn up anything (NY, Boston, New Orleans, etc.).