Link takes you to the TopupTV website where you can sign up. Offer entitles you too:
ESPN TV Adapter (CAM) worth £19.99
One month ESPN worth £9.99
Connection worth £20
You need to set-up a direct debit to take advantage of the offer however you can cancel within the 1st 24hrs of activation and won't be charged anything.
I've had a few problems getting set-up using the website so it might be worth using the phone number 08444150001 (although I think this is premium rate??)
Found on page 26 of todays Daily Mirror offer ends March 15th or while stocks last.