The Alcatel One Touch Pop C1 was £59.99 at Argos, now just £19.99. A £10 top-up is usually required, however Argos FastTrack supposedly leapfrogs that particular obstacle. Cheeky!
Alcatel One Touch Pop C1 specs include a 3.5in display, 2MP rear camera, and 4GB expandable storage.
Locked to EE, but unlockable for £1.65 on eBay.
Click and collect only.
(Thanks to raj75 at HUKD)