Our cat Pique has always been an indoor cat (though she likes to go out on the balcony if, and only if, it's not too cold out), so she has never had to wear a collar. However, yesterday I was altering the collar of a button-down shirt by cutting a more open, rounder collar and hemming it by hand with blue bias tape.
Shane had the genius idea of making the cat wear the leftover collar. After we finished laughing, I realized that she looked quite distinguished. She doesn't seem to mind wearing it for a while, but of course we removed it after a bit.