US agents have raided five homes across America as part of the first federal criminal copyright action taken against file-sharing networks.
Kill Bill is among the films available via the file-sharing network
Equipment was seized as part of an investigation into illegal sharing of copyrighted movies, music and games over a peer-to-peer (P2P) network.
Users of P2P can access files directly from computers of other network users.
"P2P or peer-to-peer does not stand for 'permission to pilfer'," said Attorney General John Ashcroft.
Equipment alleged to have been used to share hundreds of thousands of songs, movies and other copyrighted material over the internet was seized in Texas, New York and Wisconsin.
The people targeted in the raids were believed to have operated "hubs" in a file-sharing network based on Direct Connect software.
Each of the five hubs holds enough storage for the equivalent of 60,000 movies or 10.5 million songs, Mr Ashcroft said.
Among the files offered on the network were the films Kill Bill, The Lord of the Rings: The Two Towers and The Last Samurai, according to an affidavit filed in connection with one of the search warrants.
No arrests were made, but Mr Ashcroft warned that those who copy music, movies and software over P2P networks without permission could face imprisonment.
"We do not believe it is appropriate for the Department of Justice to stand by while such theft is taking place," he added.
Direct Connect parent company NeoModus Inc was not immediately available for comment.
In order to join the network, members must promise to provide between one and 100 gigabytes of material to trade, the equivalent of up to 250,000 songs, Mr Ashcroft said.
"They are clearly directing and operating an enterprise which countenances illegal activity and makes as a condition of membership the willingness to make available material to be stolen," he said.
Record labels have taken legal action in more than 3,000 copyright cases against individuals in the US over the past year, typically winning settlements of around $5,000 (£2,780) per case.
On Wednesday, the Recording Industry Association of America said it had sued another 744 people and re-filed legal action against 152 others who had ignored or declined offers to settle.