I like that on a lot of levels. If box = coffin, then "death is
  the great equalizer". If it's "king = pawn" then it's
  pro-communism or socialism. It could be personal empowerment, as
  in, "You ain't the boss of me, beyotch". It could be a simple
  statement of equality, "We all put our pants on one leg at a
  time." Or a number of other things. But my favorite is still #1:
  GAME = LIFE, BOX = COFFIN, KING = THE POWERFUL, PAWN = "I" OR
  "US". "