Michelangelo Used These Custom, Multi-Headed Brushes While Painting 'The Last Judgment' to Replicate His Intricate Sculpting Techniques
While restoring the Sistine Chapel, researchers discovered wavy groupings of brushstrokes which indicated that the artist used the special brushes to create a distinct crosshatching pattern
We haven't written up this one. Smithsonian has the full story — the link below goes straight to it.