Related Clues:

• Unpaid factory worker
• Michelangelo's 'Pieta,' e.g.
• Kind of bomb
• U.S. Steel founder
• 'Lost in Space' figure
• Iron man?
• Automaton
• Futuristic slave
• Early N.Y. Public Library benefactor
• Bust
• Martian explorer, e.g.
• Uncomplaining servant
• Metalhead?
• Mechanical man
• NASA exploring tool