Pilot Crackers
Pilot crackers are a form of hardtack, which was a popular staple eaten on sea voyages. They became popular in the Northeastern U.S. from New York to Maine as an accompaniment for soups and chowders. They're also popular in Hawaii and in Alaska.
Until Recently, Nabisco sold a product called "Crown Pilot Crackers". However, just as they discontinued "Royal Lunch Mik Crackers", they have also discontinued "Crown Pilot Crackers".
For alternate sources, see:
Pilot Crackers #2
Pilot Crackers #1