Having lost my fitbit flex I had been on the look out for offers, but it seems mainly to still retail around £59.99 - £69.99. Managed to find it on Curry's for £39.99 but then stumbled upon the Halfords shop on Ebay selling the slate version for just £30 (free delivery). (I know Argos also have it on their Black Friday deals for £39.99)
The Flex is the basic one, but i've got on fine with mine having synced it with my phone and find it motivational to do steps and join challenges in the the week. great price at just £30.
Only 9 remain at time of posting.
Also 1.05% cashback available on topcashback and 300 nectar points via Ebay. The slate is the only colour but you can buy different coloured wristbands for £1-2.