A recent batch of Video iPods from Apple have shipped with a Windows virus. "The virus has been identified as the Rjump or Rajump worm by antivirus software makers and as RavMonE virus by Apple. Incidents of the virus infecting iPod owners occurred as early as September 22, according to comments on Apple's support forum." Nice. (Source: SecurityFocus, Apple)
UPDATE (10/19/06) Microsoft's Jonathan Poon responds to Apple's statement, "we are upset at Windows for not being more hardy against such viruses".