The tracking of who downloads what from peer to peer networks is central to the various proposals to police illegal file sharing in the UK. According to the BBC and Which it seems one couple who had never played a computer game and didn't have a wireless network that could have been easily hijacked received a letter asking for £500 or they would face a court case.
The couple from Scotland contacted Which over the accusation from people working on behalf of Atari that they had shared a copy of Race07. It would appear that the letter arose due to the IP address being tracked to this couples broadband connection, though due to the lack of response by Atari it is not clear if this was the sole evidence.
The BBC article gives one clue as to how the situation could have arisen and that is that operations such as Pirate Bay insert random IP addresses into the various logs thus making it harder to track users of the service. Illegal file sharing has always been something of a cat and mouse game, and firms pursuing people run a serious risk of creating a backlash among those who actually buy their products.
The question now is how many of the other cases that are being brought to the courts have the same problems with evidence. For broadband providers that use dynamic IP addresses another issue arises- that of ensuring that the time supplied for when the IP was in use matches the timezone of their server logs.