I'm making kitty toys.
The one in the middle has a little bell inside -- it doesn't jingle, of course, but it makes a kind of rattling noise. The feathered one was my own idea. They're stuffed with wound bias-cut strips of calico, which makes them both tooth-friendly and compact enough to roll well. The feathered one I made by glueing the feathers to the end of the bias strip before I started winding it. They should be pretty hard to pull out.