A journalist holds a digital "Walk The Wall" Guide in Berlin July 9, 2008. Similar to audio guides devices found in museums, the 158-gram digital "Walk the Wall" guide covers 15 kilometres (9 miles) of Berlin and offers detailed descriptions, pictures, eye-witness interviews and film clips of various areas of where the Berlin Wall once stood. The Global Position System (GPS) link gives constant updates on a Berlin map -- complete with a blinking yellow box of the holder's exact location -- and includes a treasure trove of material on the Wall that divided Berlin for 28 years. REUTERS/Wolfgang Rattay (GERMANY)