Public-Domain Disney Characters?

[Scrooge MacDuck]

Setting aside characters who were public-domain to start with (like the Wonderland Alice), has a list ever been created of all Disney characters which have fallen into the public-domain in either the U.S. or Europe? Who would appear on such a list? The Alice in Cartoonland cast, certainly; presumably including the original-flavor, ursine Bootleg Pete (I wouldn't take my chances in foregrounding him on a cover or creating merchandise, but I expect you'd be alright putting him in a novel or the like). It seems fairly well-known that the Mad Doctor is fair game. Is there anyone else? I put this in this section because I expect most would come from the cartoons, but I even wonder whether any early comic-strip characters have joined the public domain…

[drleevezan]

A cursory search reveals that "The Cookie Carnival" and "Susie the Little Blue Coupe" have fallen into the public domain (due to failed copyright renewal, I'd imagine), so the characters therein would presumably be fair game as well.