I spotted this one on Google groups http://groups.google.com/group/google-maps-api/browse_thread/thread/aa34d789185a1349 (http://groups.google.com/group/google-maps-api/browse_thread/thread/aa34d789185a1349) about Canadian topo maps showed in vectorial topographic maps
here an example I saw at http://www.clubmontagnecanadien.qc.ca/sentier/toporama.htm (http://www.clubmontagnecanadien.qc.ca/sentier/toporama.htm)
besides GPS visualiser (I would wished for a presentation similar to ACME Mapper) and Topoquest http://www.topoquest.com (http://www.topoquest.com) who shows some Canadian topo maps online and MyTopo.com http://www.mytopo.com/maps.cfm (http://www.mytopo.com/maps.cfm)