Ive seen a trained ostrich! that was in a circus though. Ive heard of trained peacocks too in circuses.... Im sure youve all seen the trained goldfish on youtube!
Chessington have a Binturong that is whistle-trained to climb along a set route.
They also have a Hooded Rat that runs right along the rope encircling the display area.(demonstrating how Rats board ships). That isn't whistle-trained though...
It took Denver Zoo 3 years to train a female porcupine. All the Porcupine could take was walk to a piece of wood, climb on it, and take a treat. I think that it is even more odd that it didn't take long at all for snakes to move to one side of there cage when a black light comes on so the keeper can clean it out.