My cat will play fetch for as long as I throw her little mouse toy. She'll even let me throw it from bed and she'll bring it right back up for me to throw again.
My handsome boy has a toy fish he brings to me. Well, he brings it wherever he sleeps and sometimes that is on my legs. Sometimes he just brings it to me. He really likes that fish.
He will play fetch with those plastic springs. Those disappeared for a while. I had to do some work behind my fridge yesterday and found over 15 of them hiding under there.