God I want these. Being male, I'm not normally one for cushions on a sofa (they just get in the way of my reclining) but these have completely and utterly changed my mind.
They're 12" across - about the size of a pizza - and made of light grey and black felt. They're machine washable, and will cost you $60, plus $15 shipping. That's £50 or so, total. Only three sets left though, at the time of writing, so be quick!