Use the code 20OffGames-1 at checkout for this price. (Only usable once per account, but it only takes another email address to make another account and use another 20% code!)
Looking through the Tesco deals and Starcraft 2 certainly deserves a mention as I don't believe it's been below £34.99 since release 6 months ago. (Seriously, do a search!)
I've put countless hours into the multiplayer of SC2 and even if you completely disregard the multiplayer, the single player campaign is pretty darn epic - 15 to 20 hours in length and thrilling throughout. This game single handedly got me back into PC gaming!
8% Topcashback / Quidco too.
Thanks to MissGemgem for giving us the heads up for this code - much appreciated.