Wikileaks, the whistleblowing website, is preparing to release 400,000 files on the Iraq war in a publication that promises to eclipse the release in the summer of 70,000 classified US military files on the Afghanistan conflict. Here are 10 previous high-profile leaks.
Iraq Apache helicopter attack
Horrifying video footage showing 15 people including two Reuters journalists being shot dead by a US Army Apache helicopter gunman, taken from the helicopter's gun camera, appalled the world when it was released on Wikileaks.
The crew were heard laughing at the "dead b-----ds" and saying "light 'em up!" and "keep shooting, keep shooting".
The US military has refused to discipline the helicopter's crew, saying that there were "insurgents and reporters in an area where US forces were about to be ambushed.
"At the time we weren't able to discern whether (Reuters employees) were carrying cameras or weapons."
The brother of one of the dead Reuters journalists was sceptical: "My question is how could those highly skilled American pilots with all their hi-tech information not distinguish between a camera and a rocket launcher."
Guantanamo Bay operating procedures
The "Standard Operating Procedures for Camp Delta", the US Army manual for soldiers dealing with prisoners at Camp Delta, was released on Wikileaks in 2007.
Human rights groups were concerned to discover that according to official guidelines, prisoners could be denied access to the Red Cross for up to four weeks. It also showed that inmates could earn "special rewards" for good behaviour and cooperation - and that one such "reward" was a roll of toilet paper.
In 2008, Wikileaks published "the collected secret 'bibles' of Scientology", including some of internal workings and strange practices of the controversial Church. It showed that there were eight "levels" of "Operating Thetans", with Level Eight being the highest, that Scientologists can aspire to.
It also instructed adherents to carry out difficult-to-understand "drills" including: "Find a tight packed crowd of people. Write it as a crowd and then as individuals until you have a cognition. Note it down." The drills were written by the Church founder L Ron Hubbard himself.
Lawyers for the Church of Scientology attempted to force Wikileaks to take the information down, calling it the "Advanced Technology of the Scientology religion", but the site refused.
Climate Research Unit emails
More than 1,000 emails sent over 10 years by staff at the University of East Anglia's Climate Research Unit were posted on Wikileaks after being accessed by a hacker. They appeared to show that scientists engaged in "tricks" to help bolster arguments that global warming is real and man-made.
One said: "I've just completed Mike's Nature [the science journal] trick of adding in the real temps to each series for the last 20 years (ie, from 1981 onwards) and from 1961 for Keith's to hide the decline." The report was described by sceptical commenters as "the worst scientific scandal of our generation".
The head of the CRU, Professor Phil Jones, stepped down from his role in the wake of the leak, although following a House of Commons inquiry which found that he had no case to answer he was reinstated.
Australian internet blacklist
Last year, as the Australian government plotted a "great firewall of Australia" intended to prevent internet users in that country from seeing websites which the government deemed unsuitable, Wikileaks got hold of the proposed blacklist.
It published them despite warnings from Bjorn Landfeldt, a University of Sydney professor involved in creating the list, that the list "constitute[d] a condensed encyclopedia of depravity and potentially very dangerous material" and "the concerned parent's worst nightmare" as children would inevitably seek it out.
About half of the listed items were not child pornography or anything similar, but included Wikipedia entries, YouTube videos, fringe religious sites, fetish, straight and gay pornography, and even a travel agent's website and one of a dentist in Queensland.
Trafigura's Minton Report
In 2009 the internet went crazy over oil trading company Trafigura's attempts to block publication of an internal study about the health effects of waste dumping in Africa. The draft report, written by scientific consultant John Minton, said that the chemical processes Trafigura used to clean the dumped gasoline was amateurish and would probably have left dangerous sulphur compounds untreated.
It was said that these compounds could cause severe burns to the skin and to the lungs, permanent ulceration, corneal damage, vomiting, diarrhoea, loss of consciousness and death to people who came into contact with it. The Guardian gained possession of the report, but Trafigura took the newspaper to court to gain an injunction. However, Wikileaks also had received the report, and within hours the information that The Guardian was legally prevented from publishing was all over Twitter.
The names, addresses and occupations of 13,500 members of the far-Right British National Party were released on to Wikileaks in 2008. The list included the names of several police officers, senior members of the military, doctors and professors.
It came as senior military figures warned that the BNP's politics were "fundamentally at odds" with the values of the British military, and BNP figures said that the "establishment" was trying to "derail" the party. At least one person on the list was fired from their job after it was revealed that they were a member of the BNP.
Sarah Palin's email account
Ahead of the 2008 US Presidential Election, Republican candidate John McCain's running mate Sarah Palin had her private Yahoo email account hacked by Anonymous, an online group best known for an ongoing battle with the Church of Scientology.
Two emails, her contact list and various family photos were posted to Wikileaks. The McCain campaign described it as a "shocking invasion of the governor's privacy and a violation of law". It was found that Mrs Palin had been using the private account for official business, and it was alleged that this was to avoid American public record laws.
9/11 pager data
More than 500,000 pager messages sent in the United States on the day of the September 11 attacks were published to Wikileaks in November last year. Some were from federal and local officials, but most were from ordinary people.
There was a debate over whether the release was legitimately in the public interest, revealing personal messages such as "I'm ok & love you..xoxoxoxoxoxoxoxox". A Wikileaks spokesman defended the leak, saying that it represented "one more building block to getting a full picture of what happened on that day."
'How to stop leaks' document
In a delightful twist, a British military manual - the Defence Manual of Security, or Joint Services Protocol 440 (JSP440) - specifically dealing with how best to avoid leaks was leaked onto the site in October last year.
It warned that the Chinese "[have] a voracious appetite for all kinds of information; political, military, commercial, scientific and technical" and that spying is no longer like "the novels of John Le Carre". Journalists are listed in the document as one of the "threats" to security, alongside foreign intelligence services, criminals, terrorist groups and disaffected staff. In an even more self-referential moment, a Pentagon document naming Wikileaks itself as a threat to national security was leaked - to Wikileaks.