I found this link on Andy Di Conti's site. He has a "3 in 1 animal" as a
sketchbook assignment.
http://www.switchzoo.com/
You will need to download free Macromedia Flash Player 6 if you do not
already have it. Switch Zoo allows you to add different head, tail and legs
to various animals. There are fun sound effects as the animals morph from
one to another and many hidden animals in the morphing process.
Check it out and have some fun! I am looking forward to seeing some of
Andy's students' sketches posted to his site.