& @wait
 
  Syntax: @wait <seconds>=<command>
           @wait <object>[/<seconds>]=<command>
           @wait <object>/<attribute>=<command>
 
  The first form of @wait executes <command> after <seconds> seconds. 
  The second form increments the semaphore count for <object> and 
  executes <command> after <object> is notified with the @notify 
  command.  If the semaphore count for <object> is negative (because 
  it has been notified more times than it has been waited on), then 
  <command> is run immediately.
  
  If <seconds> is specified in the second form, the command is
  automatically run after <seconds> seconds even if the semaphore 
  isn't notified. 
  
  The third form allows for blocking multiple sets of commands on 
  the same object, using seperate attributes to keep track of the 
  semaphore.

  This command charges a deposit of 10 coins, which is refunded when
  <command> is executed.
 
  See also: @drain, @notify, @ps, SEMAPHORES