A court fined Arizona resident Jeffrey Howell $40,850 for sharing a Kazaaful of files on the internet. The case was closed early after the judge discovered that Howell wiped his machine. From Ars:
Howell, who served as his own counsel throughout the trial, did himself no favors by intentionally destroying evidence of his computer activity after being ordered by a judge to preserve it. According to the RIAA, Howell uninstalled KaZaA and deleted everything in the shared folder, reformatted his hard drive, downloaded and used a file-wiping program, and then nuked all the KaZaA logs on his PC. Anyone who has seen even a single episode of Perry Mason knows that this is a huge no-no
Moral of the story: If you actually are sharing music files, you're probably better off paying the few thousand dollars that the RIAA extorts from you to avoid a trial. It will cost you more just to hire someone to defend you competently, which is the point.