Automated Genealogy
Automated Genealogy hosts several projects to index Canadian censuses. Over the last several years Library and Archives Canada has digitized their microfilms of the original census forms for several of the Canadian censuses and Automated Genealogy has organized volunteers to produce indices to the people enumerated in these censuses.
Scotlands People
Historical Record Collections (FamilySearch.org)
Census of England, Wales and Scotland online
Census Links
Links to many sites worldwide that offer census transcriptions.