Telemarketing
Canada
Canadian Marketing Association's Do not contact list
Call your provincial telco and ask to be added to their "Telemarketing exclusion list". If they have a URL for this list, please add it here to the wiki. Typically once you've been added to the list it takes 3 months to propagate, and then you will be on the list for 3 years until you must renew.
How to annoy those annoying telemarketers
For one always have the upper hand. Put them on speaker phone so that you don't have to cramp your ear. While they talk walk into the kitchen and make yourself a milkshake, then go back and if they are still there talking then try to ask them what you missed and such. Finally after showing lots of interested and no attention say you weren't really interested. The telemarketer gets paid for the time, if you waste their time, they don't get paid.. you'll land on their do-not-call list pretty sooner than later.