tippy top

— Someone in the crowd took a small plastic top from his pocket. "Have you seen these ‘tippy tops’ that the dealers are selling? I'll bet you a nickel that if you spin it, it will turn upside down and spin on the tip of its pin." "No bet," said Nick. "I bought a tippy top myself. But I'll tell you what I'll do. You spin the top clockwise. I'll bet you a nickel you can't tell me now in what direction it will be spinning after it flips over."