Here's a photo of the little knit teddy bear that functions as a zipper pull on one of the fabulous European thrift items I picked up. It makes a simple dress so cute and chic. The dress is brown and rust.
I could see extending this idea in all sort of ways... Any sort of little knit critter could be attached to either a home-made garment or a store-bought one. Imagine a little elephant on a hooded fleece sweatshirt. Or wild little dollies that were attached in a jumper pocket so they could pop in and out.
Just make sure your critters are firmly attached and drool-proof!
Oh, and if you're the type who likes to knit tiny little things like this with OO needles, drop me a line... maybe I can trade you something atrociously bulky for it!