American Museum of Natural History

A time capsule under the Tyrannosaurus rex

"The last major renovations to the hall happened about 15 years ago. We found old newspapers and people's names carved into things. So when we redid the T. rex, we put a time capsule under [the base]. There's a plaque with the names of everyone who worked on it, and a bottle of a very nice beverage for someone to drink after we're all dead."—Mark Norell, chairman and curator-in-charge, Fossil Reptiles, Amphibians, and Birds

Where to find it: Koch Dinosaur Wing

Hidden chipmunk in the okapi diorama

"All the dioramas are real places from a specific expedition. The wolf diorama even has the right constellation and moon phase from the day the artist visited. But in the okapi diorama, one of the artists drew his signature creature in the background: Somewhere, if you really search, in our Congo rain forest, there's a little [North American] eastern chipmunk."—Stephen C. Quinn, senior project manager and artist

Where to find it: Akelely Hall of African Mammals (you might need binoculars to spot it!)

The sinking of the Blue Whale

"During the Blue Whale's installation in 1969, one of the managers was concerned that the mounts be architecturally sound. He checked every day with a piece of wood that measured from the floor to just under the whale's chin, so he'd tell if it was drooping. Some workers would dip the wooden pole in glue and sawdust every day, making the wood a little longer, so [their boss] thought the whale was slowly falling. I don't think the manager ever found out [about the prank]."—Stephen C. Quinn, senior project manager and artist

Where to find it: Milstein Hall of Ocean Life

Museum of Modern Art

The unusual purchase of Meret Oppenheim's Object (Fur-covered cup, saucer and spoon)

"Director Alfred Barr wanted to buy it in 1936, but the trustees disagreed. Barr was so convinced that it belonged in the collection that he bought it with his own money for $50. Ten years later, enough time had passed that the trustees agreed. All that time it was in the museum, under the label 'extended loan,' kind of in this purgatory. It's one of the great stars of our Surrealism collection; to think that our director had to sneak it in!"—Ann Temkin, chief curator, Painting and Sculpture Where to find it: Fifth-Floor Painting and Sculpture Galleries

Who really painted Cameron Platter's Kwakuhlekisa

"[Platter is] a young artist who has been mining the idiom of black-and-white linoleum cuts in South Africa. What's unusual is this wall stencil came to us as a digital file on a jump drive, with instructions. We projected it, going back and forth with him using pictures on our iPhones. We had a very talented sign painter here, Paulette Giguere, execute the work: She actually traced it and painted it on the wall using common house paint."—Judith B. Hecker, assistant curator, Department of Prints and Illustrated Books

Where to find it: Second Floor Prints and Illustrated Books Gallery

Where it's @

"We don't own the @ symbol; we have it in the collection. I like to say that it might be the only free, but not priceless, object at MoMA. Our purpose is to put together the best examples of modern design—[the character] comes from the Middle Ages but has been reborn. [The one] we show in the museum is silk-screened on the wall in American Typewriter font. You should think of it as a shadow of the design."—Paola Antonelli, senior curator, Department of Architecture and Design

Where to find it: Third Floor Architecture and Design Gallery

The Metropolitan Museum of Art

A seaman's handiwork

"There are all kinds of carved names on the Temple of Dendur, but the only inscription to be positively attached to a specific person belongs to Armar Lowry Corry, a lieutenant in the British Royal Navy, who scratched his name into the stone on the right side of the temple's main entrance."—Bret Watson, founder and president of Watson Adventures

Where to find it: Temple of Dendur

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