I don't know what happened to the original poster, but you can check with your local shelter (if you have one) and see if they accept blanket donations. Mine was surprised when I showed up with the first one, but we have adopted several animals from them and I was confident that they would take them. (They did.)
The Snuggles Project, which is where the idea for the Oddball Pet Snuggles project came from, has suggested sizes listed on their website. (We're doing 24" x 24" for the Oddball project.)
We are asking you to donate a little of your time and your leftover scraps of yarn or fabric to make snuggles for your local humane societies and animal shelters. Crochet, knit, quilt or sew cloth blankets in the following guideline sizes:
14" x 14" for cats and small animals
24" x 24" for cats and small to medium dogs
36" x 36" for medium to large dogs
These sizes are just guidelines. The actual Snuggles don't have to be exact. They could be made out of acrylic yarn or cotton in any pattern or color that you choose. The ends should be double-knotted and fastened off long and woven through the work to prevent unraveling from washing and wear. They are best when they are made thick for comfort and warmth.