File-sharing is booming, with people downloading millions of files despite efforts by the entertainment industry to stop the practice, say experts.
Hollywood is increasingly worried about illegal movie file-sharing
Films and other files larger than 100MB are becoming the most requested downloads on networks around the world, said UK net analysts CacheLogic.
It measures peer-to-peer traffic on the networks of internet service providers
It estimates that at least 10 million people are logged on to a peer-to-peer (P2P) network at any time.
Alive and well
"Video has overtaken music," CacheLogic founder and chief technology officer Andrew Parker told BBC News Online.
The firm has come up with its picture of file-sharing by inspecting activity deep in the network rather than just at the ports.
It found that file-sharing is very much alive and well, despite claims from the music industry that it is declining.
Copies of Spider-Man 2 can be found on file-sharing networks
P2P is the largest consumer of data on ISP's networks, significantly outweighing web traffic and every year costing an estimated £332 million globally, according to CacheLogic.
In the sphere of music, traditionally assumed to account for the vast majority of file-sharing, it is no longer about the big guns such as Kazaa, which has declined in popularity since being targeted by the RIAA (Recording Industry Association of America).
File-swappers have moved their attention to other peer-to-peer software, such as Bittorrent.
While the FastTrack network (which carries Kazaa ) still accounts for 24% of all P2P traffic, the lesser known Bittorrent and eDonkey together account for 72% of file-sharing, according to CacheLogic's report.
The idea that P2P is all about MP3 files is a myth, said CacheLogic.
It found that the majority of the traffic comes from files over 100MB in size, suggesting that net users are as likely to download larger movie, software and game files as they are the smaller MP3s.
On the release of one major Hollywood blockbuster, 30% of the P2P traffic at one ISP came from a single 600MB file.
"The growth is away from music. There is a new chairman coming to the MPAA
(Motion Picture Association of America) and he will probably be very aggressive," said a spokesman for CacheLogic.
The MPAA recently suggested that one in four net users downloaded movies and it has warned that the extent of film piracy online looks set to increase as people switch to broadband.
According to research firm Jupiter, 15% of European P2P users download one full length movie each month. In Spain, the number jumps to 38%.
"There will be a ramping up of activity from the MPAA but there will also be lessons learnt from the RIAA's approach and I don't expect anything so heavy-handed as that," said Jupiter Research analyst Mark Mulligan.
He is not convinced that video downloads will take over from music at any time soon.
"I would be very surprised if movie downloads were the dominant form of file-sharing. This is largely because downloading is quite a painful experience for anyone with less than one megabit of bandwidth," he said.
It is also a question of convenience. Music files, being so much smaller, are easier to store on hard drives.
Music downloading is becoming an ingrained cultural norm for young people, who see it as an easy way of building up their collection.
"There is a whole generation of file-sharers growing up with no concept of music as a paid-for commodity," he said.
"Having said that, file-sharing remains a challenge to music, movie and TV industries alike," he added.
Blame for the peer-to-peer problem, which is weighing down the networks of internet service providers, is often put at the feet of a few heavy users.
But over one month, a single one of CacheLogic's measurement tools, observed 3.5 million unique IP addresses.
There are more and more legitimate music download sites
"Peer-to-peer is the killer application of broadband," said Mr Parker.
"It has global use, never sleeps and has no geographical barriers."
Free software is often distributed via peer to peer networks and content providers, including the BBC, are considering using P2P protocols to distribute content.