Exa Networks in 15 months for 12 months price offer
Exa Networks is an ISP catering to business users, and is offering new sign-ups the chance to pay for a 12 month contract, but receive 15 months of service. In other words they would receive an extra three months free service. This means a potential saving of up to £380 over the period.
Paying up front for a years service does sound a lot of money, but at least Exa Networks inform us that if there is any need to cancel the service during the annual term, a pro-rata refund would be made.