An anonymous reader at Boing Boing shares his experience on how to cancel a service quickly without having people trying to retain you. He also has some insider news because he works in telecommunications company. A tips like calling outside business hours will save you time on the phone:

I’ve worked for a telecommunications company that I would prefer to go unnamed, and I’d like to offer some tips to anyone trying to disconnect a service they no longer want. The biggest tip is to call well outside of normal business hours — in my company, customer service was open 24/7, but the retention department closed in the evening. If you call, say, before bed, or during the middle of the night, you’ll just be talking to a regular CS rep who has no incentive whatsoever to keep you as a customer. It can turn a twenty minute phone call into a two minute phone call….

How to cancel a service – [Boing Boing]