Tesco have two codes that work at Tesco Direct which seem stackable if you buy certain things. The Codes are:
TD-KMPW - £5 off when you spend £35 or more on CD's, DVD's, Blu-Rays or Games Software
TD-MXTN - £10 off when you spend £75 or more on any product on Tesco Direct
As an example, i've just put Black Ops 2 for Xbox 360 (Including Nuketown 2025 Map) plus Medal of Honour Warfighter (Limited Edition) through checkout for £61.82.
Quidco at 3% brings both new release games in at under £30 each delivered. I'm sure there are plenty of other good ways of doubling up so have a look yourself. Enjoy :)