The M series cars are now a staple of the BMW lineup, representing the high-performance iterations of several of the "mainstream" models. However, back in 1978 before the M3 or M5 or M6 were ever conceived, BMW had a desire to compete against the Porsche 911 that was dominating endurance racing in the FIA Group 4 and Group 5 categories. Thus the original M1 was born as a mid-engine sports car with a Giugiaro designed body and a twin-cam inline-6 that eventually found it's way into the first generation M5/M6.
The original M1 is largely forgotten today, but the badge may be set for a revival on a car that is more of a modern descendant of the car that created BMW's sports-sedan reputation. The new 1-series coupe-based M1 is expected to take up the mantle of the original 2002tii that pre-dates even the mighty M1. Coupe and convertible M1s may appear in the second half of 2008 with hand-me down motivation from an updated 3.2L six from the last generation M3. The little coupe with the big six could hit 62mph from a standstill in 5.2seconds.
Since BMW seems to be increasingly keen on turbocharging of late, a pressurized direct injected four cylinder with E85 capability might make a more efficient, cost effective and better performing alternative to the old M3 mill.