'Stephan_Kampwirth' took computer lessons for his role as a hacker.
In the opening shot you can see the "blinkenlights" building, the "haus des lehrers" (house of the teacher) which the chaos computer club used as a 12 story tall 8x18 display for animations from 12 September 2001 to 23 February 2002.
Stefan Kraft, who played and (as Stefan Giuliani) composed the score, has a cameo appearance as 'man in the long black coat'. This is also a tribute to Wim Wenders' 'Der Himmel über Berlin'.