Play again, there was a challenge Thread here somewhen. Like... beat the game with 3 Heart pieces, or complete the Caves of Ordeal without using any heals.
Or something cool you could try: Kill Ganon while wearing the Magic Armor. Trust me the ending sequence looks friggn awesome when Link wears that Armor.
Do you have all the Items? have you completed the Fishing sea? Completed the Caves or Ordeals? Erm... what else... Won the snowboard contest?