Didier Ludot is one of the world's most famous vintage clothing dealers and an incredibly charming man to boot. (A tip: be nice to the dogs.) Rifle through the French couture from the '20s to the '70s on the racks: wonderful Chanel suits, Balenciaga dresses, and Hermès scarves. He has three boutiques: No. 20 houses his amazing collection of vintage couture, No. 24 the vintage ready-to-wear, and across the way at No. 125 you'll find his own vintage-inspired black dresses and his coffee-table book aptly titled The Little Black Dress. Métro: Palais-Royal. Other locations: 24 Galerie Montpensier, 1. 125 Galerie de Valois, 1.