The New York Times recently posted an interesting article about a new company that has started called BillFixers, which acts as your agent to cut your cable and phone bills. It gives tips for getting lower bills, and a lot of these things can be easily done yourself:
1. Say that you're canceling the service. This will get you passed to the retention department.
2. Be very nice and friendly.
3. Ask for a 'new customer' discount, even if you're an old customer.
5. Ask for a one time credit.
6. Be prepared - find out what the competition is offering.
5. Avoid new contracts.
6. Write down the details of the offer and call back for confirmation.