Not sure if this is a good deal but basically you sign up through Metro newspaper. This offer came out on 07/06/10. By going to audible.co.uk/metro.
If you have an Amazon account for fast sign up you can enter those details instead. They then credit your account with 1 credit which allows you to choose a book to download and listen to on you iPod or android device by downloading a separate Audible app from either App stores of Apple or Android Market. The offer lasts 14 days after which you automatically get subscribed to Audible. So if you dont like listening to books definitely cancel after 14 days. Cancellation can be done online in you My Account details or calling them 0800 0825 100
020 8735 9494. Hope some of you might like this!