Have you ever wondered how they make glass marbles so perfectly round? They roll them! And roll them, and roll them. Chill Video got a look inside a marble factory, where marbles begin as lumps of molten glass. They then go on a long, tumbling, turning route that keeps them spinning around so they have no chance to flatten out before they cool down enough to hold their shape. Pretty cool, huh? The song accompanying these marbles is the 1991 hit "Aloha Heja He" by German musician Achim Reichel. -via Digg