Theming

Cool repository of themes for use with the Google Maps API.

http://snazzymaps.com/

A Google Maps builder that uses Snazzy Maps for its theming options.

http://googlemapbuilder.mynameisdonald.com/

Google also has a Styled Maps Wizard to roll your own.

http://gmaps-samples-v3.googlecode.com/svn/trunk/styledmaps/wizard/index.html