I just saw the Italian Job again and am wondering, was the real owner of Napster informed with the Napster founder joke?
From the Italian Job trivia page at IMDb
Lyle (Seth Green) claims he was the creator of Napster, the first online file-sharing service for music, and that it was stolen by his college roommate, Shawn Fanning. In the flashback of Lyle sleeping and his roommate taking a disk out of the PC that has Napster on it, his roommate is portrayed by the real Shawn Fanning, the legitimate creator of Napster. When Fanning steals the disk in the scene, the bottom of a Metallica poster can be seen on the wall. Metallica drummer Lars Ulrich was famously a very vocal critic of Napster, and Metallica filed a lawsuit against the service for copyright infringement and racketeering.
So not only was he aware of the joke he also played himself in the movie.