There's little doubt that the greatest cat toy of all time is Da Bird. It's simply a lure made of real bird feathers that dangles from a stick, but cats go wild for it. Even though my cats were born in a shelter and have never seen a bird, somehow they know that they should be hunting this toy.
I do have to admit, though, that my boys are smart. They know the difference between toy and real. Because when we stop playing with them, they come meowing for more bird. A real bird wouldn't be controlled by us. Anyhow, here are some videos of Arthur (video 1) and Beowulf (video 2) playing with Da Bird.