Mammut has launched a GPS-based geocashing game by placing cashes in mountains, rocks and even cities worldwide. The most spectacular cashe has been hidden by a well-known mountaineer, Stephan Siegrist, on Mount Eiger in Switzerland. Co-ordinates that can be very helpful to get into the game are available under The best players stand to win Mammut equipment worth €3,000 and a weekend with Siegrist in the mountains.