The Knitting Network are offering balls of King Cole Opium for £1.69 for 24 hours as part of their Black Friday deals. The yarn is a chunky fashion weight cotton/acrylic/polymide blend which comes in 100g balls with 250 meters in each. There are also knitting patterns available for 25p each.
You can find all their sale yarns here.
This page includes affiliate links, if you follow them to shop it wont cost you any more but I may receive a small commission which goes towards the running costs of Pollyknitter.