Hackers swap tips at Berlin Chaos Communication Congress
Perhaps the most unexpected sight at the Chaos Communication Congress in Berlin is that of the kids.
Of course there are ponytailed hackers collapsed on couches, exhausted after long days and nights of programming and partying.
But running around them on the final day of Europe's biggest hacker conference are small children, playing while their parents delve into the latest security-busting and hardware-tweaking techniques.
The organisers of the event have even set up junior hacking activities for older children.
"Many people who were at the congress 10 years ago are still here. The hackers are getting older and having families," says "Xor", a 30-year-old coder from Ingolstadt in Bavaria who did not want his real name published.
The congress is the 28th iteration of an annual event held by Germany's Chaos Computer Club (CCC). Established three decades ago, partly as a way of providing hackers with legal protection in numbers, the CCC is one of the most influential hacker collectives in the world.
Much of the group's work involves finding new ways to circumvent and improve computer and network security, but its gatherings also play host to many whose primary interest is in building new things.
Some of the participants are working on a way for people to construct their own open-source mobile networks.
Others are building amateur Geiger counters for measuring radiation, or computer-controlled knitting machines that are hacked to produce fabrics based on X-rays and DNA sequences.
According to Nick Farr, a 33-year-old digital activist from New York who acts as a spokesperson for the congress's organisers, people's perceptions of hackers are evolving.
"The view of hackers has changed from people who commit crimes with computers to people who do interesting things with technology," Farr says.
"We're not sitting around looking to scam people. We're trying to make technology better; to figure out how to make it work and to tell everyone and encourage people to participate."
The CCC has clearly had some success in Germany when it comes to changing how hackers are viewed.
Many members are also supporters of the Pirate Party, which in September saw every one of its 15 candidates in the Berlin local elections win a seat in the city's state parliament.
Xor sees the election result as an indication that the CCC has become a "trusted institution" in Germany, although he remains sceptical that this perception will stay in place.
"I don't think it will last very long," Xor says. "They've had a steep rise in the polls and it's easy to create media hype when it's on the media's agenda. It could turn around and work in the other direction."
Hacking has indeed been very prominent in the news over the past couple of years in ways that are cheered or decried, depending on the circumstances.
Ordinary internet users have been directly affected by large-scale hacks, such as that of Sony's PlayStation Network, where the personal data of more than 70 million gamers was stolen in April.
Meanwhile, new copyright-protection laws such the Digital Economy Act in the UK and the proposed Stop Online Piracy Act (SOPA) in the United States have led many to fear a growing wave of online censorship.
Underground hacker collectives such as Anonymous promise a way of fighting back against such moves, which is one reason their activities are seen by some as heroic rather than destructive.
Wikileaks founder Julian Assange is a former hacker, and his pro-transparency organisation has had very close ties with the CCC.
In October this year, the club itself also revealed how some German law enforcement agencies were using spyware for the surveillance of suspects, in potential conflict with the country's constitution.
At events such as the Chaos Communication Congress, it can be difficult to tell the good guys apart from the bad.
In the darkened basement of the Berliner Congress Centre, away from the well-lit conference halls, dozens of hackers crouch over their laptops.
This is the one part of the building where photographs are definitely not allowed - not of the hackers, nor of their computers' screens.
Mr Farr insists that no unlawful activities, apart from occasional file-sharing, take place at the congress.
"Our network team is very good at responding to the breaking of file systems and people know that, so they don't try because we can identify their physical location," he says.
Others, however, mention a list of websites - mostly those belonging to far-right organisations - that hackers at the event are trying to deface or take down.
Whether or not this is the case, the event does not appear to have attracted the attention of law enforcement officials.
Some of those attending the congress are members of Anonymous itself and, according to Mr Farr, most people there support that group's anti-corporate, anti-censorship aims.
"The vast majority of the crowd here are sympathetic, but there are probably less than a dozen active participants. But, then again, you can't tell, because that's the nature of Anonymous," he says.
Marc Christiansen, one of the hackers working on the open-source mobile network project, says the trend of activism predates the more recent visibility of Anonymous and Wikileaks.
"It's not special to the last year; it's been a slower change," he says.
"The social effects play a greater role here. There are more talks about how to influence politics and also how to modify or hack political messages, to influence the public perception of politicians."
Mr Farr even claims the CCC has been a strong influence on the Occupy movement, although protesters in that movement may not realise it.
"You could almost say digital activism was invented by the CCC," he says.
"Digital activists come from all over the world to learn from the CCC. The club doesn't have a strong political affiliation, but it provides tools and techniques."
Whatever their affiliation, the hackers at the congress are conscious of the increased attention being paid to their kind, and some are mindful of the public's changing expectations of hackers.
Xor, for one, thinks the motto for this year's event, "Behind Enemy Lines", is inappropriate.
"That's like war talk," he says.
"Last year's tagline was 'We Come In Peace', which was a better representation of the CCC."