This isn't the cheapest price we've seen, and there's a good chance Black Friday will probably yield better offers, but Amazon currently have the best price for a Dualshock 4 controller. Considering how most other online retailers are normally asking for around £45, it's certainly a tempting offer for those in urgent need a spare or replacement.
We here at Dealspwn are big fans of the Dualshock 4, considering it a vast improvement over the DS3. Comfortable for long sessions and less likely to give you 'the claw' is a plus, but the fact it also works as a PC controller without configuring 3rd party software is nice little bonus. Thanks to knight01 @ HUKD for the heads-up!