While I visiting Thewotch.com for a little nostalgia trip of the good old days on the internet, I came across this animation of one of the characters, Katie, turning into a centaur! It's very brief, but it features ear-growth, tail-growth, and horse-legs-growth! And it's family friendly, too!
http://bonus.thewotch.com/oldDonatio...entaur_Special