Streisand Effect refers to the unintended consequence of further publicizing information by trying to have it censored. Instead of successfully removing the information from the public, it becomes even more widely available than before as a backlash against the censorship attempt.
In 2002, photographer Kenneth Adelman took more than 12,000 photographs of the California coastline in an effort to document coastal erosion as part of the government-sanctioned California Coastal Records Project. One of the photographs taken showed an aerial view of Barbara Streisand's Californian mansion:
According to the Californian Coast Line official website, the organization received its first cease-and-desist letter from Streisand's attorney in February 2003, shortly after the launch of the site and the online gallery. A $50 million lawsuit was filed against the photographer and other suits were filed against the image hosting services Pictopia and Layer42 on May 20th, 2003. The filing of lawsuits was soon reported in the news media, which inadvertently led more than 420,000 people to the website, according to the California Coast Line website.
On June 24th, 2003. Techdirt identified the photo as an "Internet hit." On December 3rd, 2003, a court ruled that posting the photograph was not a violation of privacy. After the ruling, Mindfully.org released evidence showing that the number of people who downloaded or ordered pictures of Streisand's house was greatly exaggerated prior to the lawsuit:
In fact, prior to the lawsuit, only six downloads of that frame were executed (out of a total of over 14,000 downloads for the site as a whole), two of which were downloads by her own attorneys. Similarly, prior to the lawsuit, only three reprints of the frame were ordered through Pictopia – two by Streisand herself and one by a neighbor who is in a lengthy dispute with her over controversial expansion plans for her blufftop estate.
Techdirt coined the term "Streisand Effect" on January 5th, 2005 when Mike Masnick, CEO and founder of Techdirt, wrote about a lawsuit between a urinal website and the Toronto airport, describing it as a case of "the Streisand Effect."
How long is it going to take before lawyers realize that the simple act of trying to repress something they don't like online is likely to make it so that something that most people would never, ever see (like a photo of a urinal in some random beach resort) is now seen by many more people? Let's call it the Streisand Effect.
An Urban Dictionary entry was first submitted on February 7th, 2005. Other websites included Forbes, The Telegraph and TvTropes. A Single Topic Blog TheStreisandEffect.com was launched in 2008.
Anshe Chung CNET Interview
In December 2006, Second Life entrepreneur Anshe Chung participated in an interview with CNET in the virtual sandbox world Second Life, when a group of griefers from Something Awful bombarded the virtual studio with giant flying penises and managed to crash the interview simulator. Anshe's husband attempted to have the images removed from sites like Something Awful and YouTube, and the blog Clickable Culture reported on the incident in an article titled "Anshe Chung Courts Streisand Effect" on January 5th, 2007.
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
In 2007, it was discovered that all HD-DVD players on the market were released with a digital rights protection system that could easily be hacked by entering the key: 09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0. The record industry tried to block the AACS key from spreading by moving to take down the article from Digg (where it first leaked). The take down attempt created an enormous backlash causing the number to spread even more.
Tom Cruise Scientology Video
In early 2008, a peculiar video featuring Tom Cruise speaking about Scientology was leaked to video-sharing websites. The Church of Scientology's unsuccessful attempt to have the video removed only boosted its popularity, and provided inspiration for the creation of the Anonymous run operation Project Chanology.
More information can be found in the KYM entry for Project Chanology
Glenn Beck Rape & Murder Hoax
In 2009, Glenn Beck tried to shut down a satirical website that claimed he raped and murdered a girl in 1990. His failure to do so only brought more attention to the hoax as it spread to YouTube and several other websites.
More information can be found in the KYM entry for Glenn Beck Rape & Murder Hoax.
Wikileaks & Operation Avenge Assange
In late 2010, Wikileaks became the target of DDoS attacks and lost all their support from Amazon, Paypal, Visa and Mastercard after releasing leaked US diplomatic cables. A warrant was issued for the arrest of Wikileaks' founder Julian Assange. This led to a backlash against the enemies of Wikileaks and inspired Anonymous to begin Operation Avenge Assange.
More information can be found in the KYM entry for Operation Payback: Operation Avenge Assange.
Google Insights data shows the first Streisand Effect search queries picking up in January of 2007. This may be related to the griefing incident that occurred against Anshe Chung, the "Rockefeller of Second Life", in December of 2006.
 Barbra Streisand Sues to Suppress Free Speech Protection for Widely Acclaimed Website – California Coast Line
 Barbra Streisand’s Lawsuit to Silence Coastal Website Dismissed – Mind Fully / 12-4-2003
 Streisand Suing Over Environmentalist's Aerial Shots Of Her Home – Techdirt.com / 6-1-2003
 Since When Is It Illegal To Just Mention A Trademark Online? – Techdirt.com / 1-5-2005