The Silver Arrow concept watch looks like a case of too much emphasis on design, at the cost of practicality. From the Mercedes-Benz logo on the center to the pair of titanium straps that open and close like a car's gullwing doors, the Silver Arrow wins point for its unique design. On the left and right side of the crown are "open" and "close" buttons, which disengage and secure the straps respectively.
We know the Silver Arrow watch is a design exercise, but shouldn't have designer Fabien Cacheux gone the extra mile? He could've made the watch a control platform for the car it was inspired by (the Mercedes-Benz SLS). Instead of controlling that fancy strap arrangement, the buttons could've acted as a keyless entry system for an actual car (and besides, those buttons make it easy to snatch the watch from its unsuspecting wearer, if you move fast enough).
By why stop at door control? High-end Mercedes-Benz models already start at a push of the button, so long as it detects a specially-encoded car on the driver. The Silver Arrow would a great—and definitely—functional replacement for that card. We'd also feel like suggesting adding some real driving controls on the watch, but clearly a wrist-based control scheme can't beat the ol' wheel and pedals.
Watch "Silver Arrow" - GT Series - April 2010 (Google translate)