But now that's starting to change. Consider Objet's case study on using 3D printed parts for RC model racing. Certainly, it's not Formula 1 racing, but these small vehicles involve plenty of moving parts that must perform perfectly if the race is to be won. Nimrod Racing uses their Eden 250 3D printer to produce many tiny parts for these vehicles that are not only much lighter than their metal ancestors, but they are also sufficiently robust to withstand the rigors of high-speed RC racing.
Via Objet (hat tip to Shimrit)