ASDA are selling 2x 4packs of Chunky Peanut Butter kitkats for £1. I know this deal was listed recently, but that only showed the normal chuky kitkat deal.
They are normally £1.08 per 4pack. Deal is available instore and online - but you would probably want to buy more to justify delivery costs.
BTW, these Kit Kats are pure ambrosia and expect to become addicted and beware, there are a staggering 269 calories per bar!!!