"Rama Map" is short for "Ramachandran Map". The Rama Map tool in Foldit displays a graph of the backbone angles in the protein. The Rama Map is described in more detail in the ideal loops article.
In the original Foldit interface, the Rama Map is available on the Actions menu. In the selection interface, the Rama Map is available on the Main Menu, which can be displayed using the lowercase "p" keyboard shortcut.