The Canada Base Map Service is a mash up of two ESRI services – one for map features, and a second for map labels. It is functionally the same as the Canada Base Map Service (WMS) except published via ESRI ArcGIS Server.
The Canadian National Research Council (NRC) Toporama web service is a high performance server that holds basic map data and presents it in a format very similar to the 1:50,000 series of Topographic Maps.
The Canada Transportation Base Map is a WMS server published by the GeoGratis service run by Natural Resources Canada. It represents a basic base map of Canada at approximately 1:50,000 scale
GeoBase is a service run by the Canadian Government to make mapping data and services public available. They maintain a WMS server with this data