The Waldseemüller World Map
If you’re into cartography, you’ll want to check out Toby Lester’s Google Tech Talk on the Waldseemüller world map, recently purchased by the library of congress for $10 million.
...the map's main claim to fame is that it gave America its name. But the map also represents a number of other important firsts in the history of cartography, and in the larger history of ideas. It was the first map to show the New World surrounded by water, and thus to suggest the existence of the Pacific Ocean; it was one of the very first maps to lay out a picture of the world in a full 360 degrees of longitude; and it was the first map to present the contours of the world's continents and oceans largely as we know them today. It was, in many ways, the mother of all modern world maps..