LOL, BMW black sheep.
IMHO BMW has only had a few over the years. Some of my favorite BMWs are seen as black sheep (by the sheep, anyway)...cars like the 2000CS, Glas coupes and the M42-engined e30 & e36 cars.
My personal 'black sheep' suggestions would be the L6, anything with a V12, any X5/6 station wagon, any M car without a manual transmission, and (worst of all) the e65 7-series...