Assassin's Creed Director's Cut for PC. Pick Free Super Saver delivery to get this for £2.99. I think Cheapest posted before was £4 ish.
If you've not played the original it's a really good storyline.
Note from SamODJ, this is apparantly also available on Game.co.uk, link in comments.
Thing is you can get Quidco via Game, so a few extra pence off if you wish :) Thanks Sam.