ABSTRACT: Google Maps and Google Earth have put much of the functionality of Geographic Information Systems in the hands of the end users. Maritime users are just beginning to understand the power of map mashups that bring together diverse datasets to help mariners and those who manage the waterways to better understand the uses, risks, and impacts of vessel traffic on our nation’s waterways. I will present a number of data types ranging from raster images of ocean flow modeling, to vessel traffic over time captured by the marine Automatic Identification System, to real time right whale notices for  vessels approaching Boston Harbor.