ShipIndex.org tells you which books, journals, websites, databases, and more, mention specific vessels. It's a great time-saver for genealogists, maritime historians, armchair historians, and anyone interested in learning a bit more about a specific vessel. ShipIndex was started in 1999 by Peter McCracken, then a reference librarian (with an MS in Library Science and an MA in Maritime History) at the University of Washington. When it contained about 100,000 citations, Peter started Serials Solutions with his brothers and a high school friend, and ShipIndex was set aside for a while. In 2009, Peter and his brother Mike picked it up again and turned it into a company. The database now has over 150,000 citations in the completely free database, and well over 3 million citations in the subscription database. Subscriptions are available to individuals and to institutions, and some of the great libraries of the world subscribe to ShipIndex.org for their patrons.