NSU started out as a sewing machine company in 1873, quickly moved into bicycles, and then into motorcycles and cars. Absorbed by VW in 1970 after investing too much money in rotary engines with too little return, the Audi factory in Neckarsulm still sits at the corner of NSU-Strasse and Felix Wankel Strasse, a tribute in macadam to a brand that no longer exists, and a method of internal combustion that only lives on at Mazda.
The History of NSU in My Words [NSU.nu]
Related:
NSU-Camino! [Internal]