Canada's National Do Not Call Registry
If you're getting a lot of unsolicited telemarketer calls (and who isn't?), you'll want to sign up on Canada's National Do Not Call registry. This registry is open for residential, wireless, VoIP numbers and faxes.
Unfortunately, the list does not prevent calls from political parties, registered charities, and business with whom you have an existing business relationship. Still, it's free and easy -- and it will cut down on a lot of unwanted calls.