Related Clues:

• Curious thing
• Peculiar thing
• Hole-in-one, e.g.
• Unusual sort
• 'Believe It Or Not!' item
• Rare bird
• It doesn't happen often
• It hardly ever happens
• Collector's item
• Curio
• Unusual item
• Aberration
• Uncommon occurrence
• Wonder cabinet item
• Weird trait