StrongVPN for something that will work every time. But, shock horror, you have to pay for it.
Also, this method works for MTV:
For Canadian viewers, if you are using firefox
- Install the Modify Headers addon
- In Firefox, Go to "Tools" -> "Modify headers"
- From the drop-down box on the left select "Add"
- Then enter: "X-Forwarded-For" in the first input box (without quotes)
- Enter: "12.13.14.15" in the second input box (without quotes)
- Leave the last input box empty, save the filter, and enable it
- Click the "Configuration" tab on the right then proceed to check the "Always on" button.
- Close the Modify Headers box and it should work.
Also works for TheDailyShow.com and ColbertNation.com