No, the Recording Industry Association of America and the Motion Picture Association of America aren't spying on you. They've got people for that, specifically companies such as BayTSP and SafeMedia, which infiltrate peer-to-peer networks so they can record file swappers' IP addresses and the types and number of files they're sharing. An IP address isn't proof positive of your identity, but it's good enough for most civil suits -- unless, of course, it belongs to a dead person or someone who doesn't actually own a computer.
If you never visit p-to-p nets, you're probably safe. If you do, using anonymous IP networks, Web proxy services, or open Wi-Fi connections can make your identity much harder to trace, says Peter Eckersley, staff technologist for the Electronic Frontier Foundation.
“Aside from the huge, open p-to-p networks like Gnutella/LimeWire or eDonkey/eMule, many people share files with their friends on small-scale networks,” Eckersley adds. “In those situations, copyright holders would have to send undercover agents to infiltrate those groups if they wanted to trace the participants.”
Given the revenue at stake and the history of the players involved, if you're swapping tunes with a small circle of friends, be sure to keep your attorney's phone number handy, just in case.