I have make numerous quilts for dog raffles - fundraisers for rescue groups. And the dog quilts are always a huge hit. I make the front with denim and/or heavyweight cottons, don't use any batting, and use no-pill fleece for backing. They always go over well and are really handy to have. I have several that I use in the van on the seats and on the floor so that everybody can find a spot to lay down. I also use the larger ones on the couch and big chair. It is so much easier to throw the quilt in the wash than dealing with the upholstery.
When the fleece is on sal e at Hancock, I purchase a full bolt - or two - in the heather gray color, because it goes 'with' everything. But there are so many colors that you can really go wild.
I have also made quilts/blankets out of just fleece - front and back. The older dogs seem to realy like them. They don't 'dig' inthem as much as the younger ones and they really like the cuddle feel of the fleece.