I love these tops. I'm running out of pockets . Machined, precision tops are just the next evolution of an ancient fascination with spinning objects that spans multiple cultures around the world over thousands of years. There is something very Zen like in watching these tops spin.
http://www.yoyomuseum.com/museum_view.php?action=profiles&subaction=spintop
http://www.yoyomuseum.com/museum_view.php?action=profiles&subaction=spintop