The FBI and German authorities are reportedly investigating two young German hackers who allegedly hacked into the computers of top music stars searching for unreleased material to sell. Among the artists targeted by the duo are Lady Gaga, Justin Timberlake, Ke$ha, and Kelly Clarkson. Authorities became involved when Clarkson saw some of her unreleased music circulating on the Web and notified authorities. The hackers also reportedly didn't stick to music, either. They also reportedly acquired a bit of personal data from the stars' computers to use as blackmail, including an image of Ke$ha "naked and having sex", which they unsuccessfully tried to use to extort money from her.