Book Brain www.bookbrain.co.uk

Bookbrain attempts to track down the best price on any book by searching through the content of eleven of the UK's top online bookstores including Amazon and Waterstones.

Uswitch www.uswitch.com

Utility comparison service helping users get cheap deals on gas, electricity, telephone and digital TV suppliers. When a cheaper supplier is found, you can cancel your current contract and sign-up to a new one instantly.

EasyValue www.easyvalue.com

EasyValue is an impartial online shopping price comparisons site where you can search for Books, CDs, Videos, DVDs and Video Games, with more categories coming soon.

DealTime www.dealtime.co.uk

The DealTime website scours around 500 online retailers and comes up with prices and all the information you need. There's also a tracker service where you can log the price you're willing to pay and and you will be alerted via email when the product becomes available.