Consuelo Castiglioni doesn't play the usual couture game. She's publicity-shy. She does not advertise. She won't hustle celebrities. But Castiglioni is a master of her craft, defining Marni as a house of unusual shapes and idiosyncratic prints (she teamed with singer/painter Kim Gordon to concoct bold geometric patterns for sum-mer '09). Yet her designs are also consummately wearable. The brand has thrived -- sales have shot past $100 million per year -- and celebs including Gwyneth Paltrow, Kyra Sedgwick, and Cindy Sherman have flocked to Marni unbidden. Castiglioni has also expanded cautiously into accessories, menswear, and rugs. -- by Linda Tischler