Mercedes-Benz's secrets

Standing outside in the snow on a bitter Wednesday afternoon in downtown Stuttgart can have its benefits. The passive smoking outside the hotel is not fun, but it's impossible to avoid a smile when a pair of top-secret Daimler prototypes idle past.

The first is disguised, but barely. It's a Mercedes-Benz prime mover with graffiti camouflage splashed over the cabin, and it sticks out in traffic exactly because of the crazy bodywork and because there is nothing hitched to the tail. As it glides past, surprisingly quietly, the reason is clear. Right behind the cabin is an experimental fuel cell stack, indicating this heavy hauler is being used to assess the future of hydrogen power in electric trucks for the not-too-distant future.

The new B - promised to bring far more sophistication to the bottom end of the Mercedes range later this year - is hard to pick in pictures, but up close it's easy to see the longer and lower bodywork, glass that cuts down deeper into the doors, a smoother new dash out line and the work that's gone into making it more than just an affordable city box with a three-pointed star. What a pity the camera was upstairs in my room during the excitement on what we quickly call 'Testing Strasse', as we see a fleet of baby Bs running down the road for the next two days.

Benz has eight new-model introductions planned this year and there is a real insight - official and unofficial - during the company's 125th anniversary celebrations last Saturday. The official stuff starts with the unveiling of the latest SLK roadster by F1 heros Michael Schumacher, Nico Rosberg and David Coulthard and continues when a design presentation on the car includes slides with sketches of the upcoming cabins of the B-Class, baby A-Class and even Benz's new segment-buster car, the E-Class based Shooting Brake.

The unofficial stuff happens when we get lost inside Benz's experimental headquarters and do a lap of the carpark. There are nearly a dozen B-Class prototypes, but we also get a quick peek at the lightly-disguised C-Class coupe, the thumping C63 AMG Coupe, the next ML SUV and even an updated SL roadster and a giant GL partly hidden under a car cover. What a pity the camera was, this time, locked away with the ruthlessly efficient guards at Gate 14.