Update: It looks like Sony has now pulled this offer. Maybe it was a mistake or it received a lot more interest than it as expecting. For the moment, unfortunately, you'll need to wait and see if it returns.
Original story: If you're a member of PlayStation Plus, Sony's subscription service, then you can pick up a copy of Final Fantasy 15 for just £10. If you're not a member then you can pick up the game for £30.
You can pick the game up through your console or if you're at a computer then head on over to the game's store page.
Considering the game only came out in November of last year, this is a hefty discount and while I didn't like the game much, some people, like Jason Schreier in his review, thought it was excellent.