Another sweet Carphone Warehouse PAYG upgrade deal (check your eligibility here) sees the quad-core Huawei Ascend Y550 going for £49.95, no top-up required. Neat.
Further Huawei Ascend Y550 specs include a 4.5in display (480 x 854), 1GB of RAM, microSD compatibility, and a 5MP rear camera with flash.
Available on Orange, T-Mobile, Virgin Mobile and Vodafone. O2 is a little more expensive at £69.95.
(Thanks to raj75 at HUKD)