I've admired Mr. Waldo Pancake's chirpy Puccino's Coffee shop branding for a while now, in fact I go there over other outlets just to drink down a little humour on the humourless commute, but he also does really sweet illustration and has lots of irreverent merch to download and buy...see his Flickr sets here: http://www.flickr.com/photos/waldopancake/sets/ and his site here http://www.waldopancake.com/