& @apay
 
  Syntax: @apay <object> = <command-list>
  Attribute: Apay
 
  Sets the actions to be taken after the object is given the number of
  coins specified in its Cost attribute.  If the giver tries to give 
  more than that number of coins, the excess is refunded, and if 
  less than the necessary  amount is given then it is all given back 
  and a snide message is sent to the giver.
 
  This attribute is only meaningful for players and things, and will
  never be automatically triggered on other object types.
 
  Example: 
  @apay Coke machine = @clone Can of Coke; :drops a can on the
  floor.
 
  See also: give, @cost, @opay, @pay