The Busy Ball Popper made by Playskool is a wonderful activity toy that is great for keeping my toddler busy.  The mechanics are easy: a battery operated fan creates a wind tunnel, in which rests 5 colored balls. The blower pushes the balls out of the top into a tray and down a spiral chute and into the tunnel for another ride.  We ordered extra balls, which were very affordable, and when added, they give the toy another dimension.  With extra balls, the machine blows the balls further out of the toy and all over the floor.  This, in turn makes my little girl squeal with delight.  Then she...