Though they were from different continents, Marcel Duchamp and Joseph Cornell are both well known for presenting commonplace objects as art. Duchamp found his inspiration in the "ready-made," wittily exhibiting everything from a urinal to a snow shovel, while Cornell arranged five-and-dime trinkets in small shadow boxes. But what's becoming even more well known is how well the artists knew each other. They became close friends when Duchamp fled Nazi-occupied France for New York City in 1942; Cornell worked out of his basement in Brooklyn. "Joseph Cornell/Marcel Duchamp: In Resonance," organized by the Menil Collection and the Philadelphia Museum of Art, traces resonances in the artists' work through 82 pieces. The heart of the exhibit is the Duchamp Dossier, created secretly by Cornell with 117 mementos of their relationship -- notes, photographs and trashcan finds such as crumpled laundry receipts and used pipe cleaners. Through May 16. Hours: Wednesday through Sunday from 11 a.m. to 7 p.m. Menil Collection, 1515 Sul Ross, (713)525-9400, www.menil.org. Free.