Open-source software movement has emerged relatively unscathed from the economic downturn.

New York University anthropologist Gabriella Coleman was the opening keynote speaker at Linux.Conf.Au, a trans-Tasman conference held in Wellington last week that attracted more than 600 open-source software developers and enthusiasts.

She took the plunge and immersed herself in the world of open source in 2001, perceiving it was a culture worthy of academic study.

"Anthropologists know a lot more about Maori than computer hackers," she says. But conferences like Linux.Conf.Au are critical to the movement's wellbeing.

Hackers is a term used by the community to describe people who write open-source software, not criminals who write malware.

Most hackers have kept their jobs in the downturn, and there are tens of thousands of open-source developers involved in thousands of projects. But even the highest-profile initiative under way – open source server and desktop operating system Debian – is largely being driven by a core team of about 100, she says.

A growing proportion of hackers is employed by information technology firms that have a commercial interest in the success of the open-source projects they sponsor. Conferences have allowed these virtual projects to scale, while reinforcing the community's values and ethics.

Ms Coleman said Linux.Conf.Au was more technical and less "political" than many, but that was before open-source software guru Benjamin Mako Hill took to the stage to rail against proprietary software and the evils of its "antifeatures".

Mr Hill, who is a senior researcher at MIT's Sloan School of Management, has set up a mock website where people can report unauthorised public performances of "Happy Birthday [to you]", to poke fun at the iniquities of intellectual property law. The song is still protected by copyright, says Mr Hill, making renditions at birthday parties technically illegal.

He says open source products are not always more functional than the proprietary products they are designed to supplant – and sometimes less so – but they are at least free of "antifeatures" intended to exploit users, which are much more common than many computer users might suppose.

These range from "spyware" and trial programmes that software-makers pay to have installed on new PCs, in the hope of gaining recurring revenues to digital rights management software, and code that deliberately limits the functionality of software. This can be to segment markets – so developers can charge more for software that is essentially the same but used in different circumstances – or to prevent devices using third-party adds-ons.

He says an example of an antifeature is a firmware update that Panasonic developed for its digital cameras this year that stopped them working if their owners were using batteries bought from third-party suppliers. Panasonic said it did this because some third-party batteries did not include devices to protect against overcharging.

Mr Hill believes some printer manufacturers have begun to engage in a similar tactic, using sensors to detect "non-genuine" ink cartridges and reducing the resolution of print-outs if they find them. Consumers are paying for such "antifeatures" and businesses are employing tens of thousands of people to create them, he says.

"The world of proprietary software is a world full of software that people hate."

Google Linux evangelist Jeremy Allison said Microsoft had used a range of tactics to stall the open-source software movement.

These included developing complex proprietary protocols that made it hard to integrate open-source products with Microsoft software and, controversially, persuading the ISO to endorse Office Open XML as a standard.

Despite Microsoft's protestations, he does not believe the culture at the top has changed. "Their business model depends on the maintenance of a monopoly on the desktop."

But Microsoft was not a monolith. "Microsoft internally is a series of warring tribes. They dislike the open source community, but they hate each other much more. That makes Microsoft harder to predict."

Microsoft's tactics had not worked, but it was turning to the "nuclear option" – using its array of patents to threaten lawsuits against developers of open-source software, he says.

Mr Allison says Microsoft's decision in February 2009 to sue TomTom for features, including Linux features, in its satellite navigation systems "for me, crossed the line. "That was the first nuke going off. I know Microsoft's open-source team were horrified about it when they read about it in the press, because that completely undid all their work.

"Before, Microsoft said they only had software patents for defensive purposes."

Microsoft says Linux's kernel violates 235 of its patents, and it has been trying to discuss a licensing arrangement with TomTom for more than a year.

Computer users should lobby against software patents wherever they are proposed in the world, Mr Allison says. "Eternal vigilance is the price of liberty."

Open source faces another challenge in the form of cloud computing, he says. Companies delivering IT services through the cloud are not actually selling software. That means they can build on open-source software without having any obligation to offer their innovations back to the community.