"If you're anything like me, you love a good map graphic,
particularly one that brings what would otherwise be dull and
boring data to life. The technical term for tools that render
statistics into visual form with maps are geographic information
systems (GIS). Open source has a wealth of top-notch GIS tools like
GRASS and gvSIG, but their power comes with a learning curve.
TileMill is a new tool that bucks the trend, letting complete
newcomers to GIS build slick looking static or interactive maps
with minimal fuss.
"TileMill technically runs as a Web app, but it is designed to
be installed locally, on top of Apache and PostgreSQL, and accessed
through Firefox. "Locally" specifically means that TileMill needs
to access your locally-stored data files in order to paint them
onto your map projects, and that (at present) the program has no
concept of user accounts or authentication. The Web app interface
stems from two of TileMill's open source underpinnings: the Mapnik
map renderer (of OpenStreetMap fame), and the CSS-derived syntax
used to mark up map elements."