At our house we call it the 'DOT'. It's a dollar store keychain laser pointer and when I pick it up the chain will rattle. She'll come running and I'll say "Do you want your DOT? Do you?!" and she'll chatter back at me, looking around on the floor for it.
I was hesitant to try it with her because I had heard of someone's cat getting obsessed with it and crying when playtime was over, incessantly looking for the dot.
She took to it really well and it's always her who says when the game is over by just laying down and ignoring it. It's great when she's restless and I give her a good run for her money back and forth in our apartment. A good time is had by all.