First came Napster, allowing music lovers to trade tunes online. Now the next Internet file-swapping controversy could be about ... hard-core pornography? 

The same technology that lets Internet surfers trade music online can be used by children to find pornography, two U.S. congressman have revealed. 

In an effort to thwart a potentially dangerous new phenomenon, the lawmakers have given parents some tips to keep their kids from accidentally or deliberately locating hard porn online. 

"It's not a question of gratuitous violence or bad language or bad taste," said U.S. Rep. Henry Waxman, D-Calif. "It's an explosion of the most demeaning and dehumanizing exhibitions imaginable, and it can appear on our children's computer screens whether they ask for it or not." 

Current file-sharing programs, which have become popular since the legally embattled Napster began its decline, can transfer much more than the music files that Napster was famous for. They can help users trade any type of file, including pornographic movies. 

Waxman and U.S. Rep. Steve Largent, R-Okla., released a report Friday alerting parents. Though they aren't yet calling for legislation, the congressmen want people to be aware of the programs and realize that most Internet filtering software doesn't stop them. Internet filters are designed to block Web pages, but most can't scan movies or block sharing programs. 

The design of sharing networks like BearShare, Aimster and LimeWire complicates the matter further. Unlike Napster, the individual users contact each other directly, instead of using a central computer. This is also a headache for copyright holders, including the music and movie industries, because in many cases no company exists to sue. 

Since Napster's decline in popularity, the upstart decentralized file-sharing networks have flourished. They are some of the most downloaded programs on the Internet, dwarfing Napster's popularity during its heyday. 

The lawmakers said parents shouldn't rely on the effectiveness of filters and should talk frequently with their children about how they use the computer. Putting the children's computer in a common room may also help, they said. 

The report, prepared by a House committee, says pornography is both popular and prevalent on the networks, and that children may accidentally stumble upon it when looking for something else. 

The search term "porn" ranks second only to a word for pirated movies on the Gnutella network, and various other adult terms dominate the Top 30 list. 

Even if children search for other popular downloads, like typing in the names of pop stars Britney Spears or Christina Aguilera, they can find surprising results. 

"When the Special Investigations Division used the popular file-sharing program Aimster to search for videos of Britney Spears, over 70 percent of the results were pornographic files," the report states. 

The Associated Press contributed to this report