• Orson Welles - Citizen Kane: 26 years old
• Salvador Dali - The Persistence of Memory: 27 years old
• Kawabata Yasunari - The Dancing Girl of Izu: 27 years old - Snow Country: 35 years old
• Man Ray - First significant photographs: 28 years old
• Luis Bunuel - Un Chien Andalou: 29 years old (via)
• Alan Moore - V for Vendetta: 29 years old (via)
• Steven Spielberg - Jaws: 29 years old (via)
• Kafka - The Metamorphosis: 32 years old (via)
• René Barjavel - Ravage: 32 years old - Grandfather Paradox: 32 years old
• David Lynch - Eraserhead: 32 years old (via)
• Murnau - Nosferatu: 34 years old (via)
• Henri Dunant - International Red Cross: 36 years old (via)
• George Mélies - A trip to the moon: 42 years old (via)
• Gustav Klimt - The Three Ages of Woman: 43 years old - The Kiss: 46 years old
• Marquis de Sade - Les Infortunes de la Vertu : 47 years old

I am getting late… :(

(Any more examples? Please post them in the comments)