The solution, created by Stamen Design's Michal Migurski, uses Mapnik (an open source GIS toolkit) and Open Street Map data. Mapnik, especially, is notoriously difficult to get working correctly. With the Amazon image created by Migurski, everything is ready to go. All you need to do is tell it which Open Street Map file and stylesheet to use--and Tile Drawer makes several examples available.
If you'd rather not roll your own tile server, you can achieve a similar effect using CloudMade (our CloudMade API profile). The service, also based on Open Street Map data, has an innovative style editor.
The similarity between CloudMade and the new Tile Drawer isn't accidental. Migurski and his Stamen colleagues designed the six default styles available in the style editor.
Hat tip: Andy Baio