Sub-brands are emerging as the latest trend, particularly among German automakers. BMW has rolled out its new i family of electric vehicles. Audi looks poised to spin the TT off into its own line with added bodystyles. Mercedes-Benz is expected to bring the Maybach name, once its own brand, back as a model designation at the top of the S-Class range. And now Volkswagen is rumored to be planning more retro models to follow in the footsteps of the Beetle.