papermario.zip is a release file of the Minecraft map Paper Mario: The thousand year door, made for Minecraft 1.7.4. It was published on January 27, 2014 and is 5.6 MB in size. For the full description, screenshots and every other version, visit the Paper Mario: The thousand year door map page.
How to install: Extract the .zip and move the world folder into .minecraft/saves; the map then appears in your Singleplayer list.