Colour Brewer is a colour selection guide with beautiful continuous and divergent colour scales.
Mapshaper is a shapefile simplification tool that lets you upload your own shapefiles.
Inquiron Online File Converter allows you to simply drag and drop files to convert .SHP files to .KML files or to geocode spreadsheets. This is really slick!
The Noun Project is a site where you can download an icon for everything, and many are free.

GIF Maker is a free website that allows you to created animated maps. allows you to provide a link to a map and it will make it zoomable. This is a great way to show very detailed maps online without creating a real web map.

GeoBC is the government portal for free shapefiles and imagery covering British Columbia.
USGS Download Portal for many types of US Geological Survey data including shapefiles and imagery for the US.
GEOFABRIK allows you to select and download Open Street Map data for entire continents (Except North America) or smaller geographic areas in shapefile format.

Census Illustrated Glossary is a great place to look up census geography terms and learn about nested geographies.
Interactive Census Map is primarily designed to help you navigate through the Census geography structure but it also allows you to easily locate and access Census Tract profiles.
World Bank Database Provides access to global development data for most countries in the world.
Interactive Map of the World Bank database provides access to global development data in visual form using a google earth mashup.

SHP Escape is a very slick little tool that converts shapefiles into geojson and topojson files, or direct upload to your google fusion tables account.