Just seen this ad in todays express,page 28 (scanner broke so can't load piccy)
Buy 2 x 10 packs @ £1.25 each = £2.50 and 1 free Kit Kat mug.
Offer while stocks last etc. Until 30/09/2007
In store at Morrisons.
Can't find any pics of the mug anywere,but Red Coffee mug with Kit Kat logo on it :)