"Happy Slapping" is a type of violent crime often committed by "Hoodie Gangs" - it involves beating people up (sometimes fatally) while filming the event on mobile phones, often these are then distributed via websites to other thugs and is a non-lethal variation of the disturbing psychological condition often labeled "thrill killing". But they may also be sent to victims as a form of threatening and cyberbullying.
- United Kingdom: On 9 May 2005, a 16-year-old Plant Hill Arts College student was beaten up and left unconscious in a vicious "happy slapping" attack in Blackley. Footage of the attack was circulated on students' phones.
- United Kingdom, 18 June 2005: Police arrested three 14-year-old boys for the suspected rape of an 11-year-old girl who attended their school in Stoke Newington, London. Authorities were alerted when school staff saw footage from the students' phones.
- United Kingdom, 7 December 2005: Singer Myleene Klass was happy-slapped in Bermondsey, South London.
- United Kingdom, December 2005: A 15-year-old-girl, Chelsea O'Mahoney (her name was initially withheld, although this decision was reversed during sentencing) and her co-defendants Reece Sargeant, 21, Darren Case, 18, and David Blenman, 17, were all found guilty of the manslaughter of David Morley near Waterloo Station, in London. Barry Lee, 20, and another 17-year-old were cleared of all charges. According to press reports, "The 15-year-old girl had told Morley that she was making a documentary about 'happy slapping' before her gang of friends kicked him to death."
- Denmark, 10 May 2006: Two men aged 17 and 19 attacked a woman in Copenhagen; one kicked the victim while the other filmed the incident using a mobile phone. Two plain clothes police officers saw the incident, and the assailants were immediately arrested and the mobile phone confiscated.
- Sweden, 1 September 2006: After a 16-year-old boy happy-slapped and hospitalised a 15-year-old Balkan boy in the city of Örebro, the victim's 17-year-old sister stabbed and killed the assailant with a hunting knife and claimed self-defence. The happy-slapping was filmed and distributed online.
- Australia, 23 October 2006: Police in Victoria launched an investigation into the production and distribution of a DVD entitled "Cunt: The Movie" featuring footage of several youths sexually assaulting a girl and setting her hair on fire. DVD copies were allegedly sold at the Werribee Secondary College for $10.
- United Kingdom, 26 January 2007: Andrew Elvin, 17, was jailed for a minimum of 12 years for the murder of Luke Salisbury, who died three days after being attacked by Elvin on 2 March 2006. Caine Hallett, 18, was sentenced to five years for manslaughter for the same incident, while Danielle Reeves, 18, faced a retrial in May 2007 for manslaughter.
- United Kingdom, 14 February 2007: Eight youths set upon a 31-year-old man in Brighton, who turned out to be an amateur boxer. Two of the youths were hospitalised by the intended victim and four were arrested for affray.
- United Kingdom, July 2007: Anthony Anderson, 27, of Hartlepool, urinated on a dying woman while a friend made a video of the incident. He is reported to have yelled "This is YouTube material!" 
- United Kingdom, November 2007: Emily Nakanda, 15, a contestant on the TV show The X Factor, withdrew from the competition after a happy slapping video in which Nakanda was shown attacking a teenage girl was discovered on the internet.
- United Kingdom, February 2008: A 15-year-old girl admitted filming the death of Gavin Waterhouse, 29, in a "happy slapping" attack which ruptured his spleen, She was sentenced to two years detention. The judge stated that the courts had to make an example of such youths.
- United Kingdom, May 2008: A teenage girl fell to her death from an attic window while trying to escape a "happy slapping" girl gang
- United Kingdom, August 2009: Ekram Haque, a retired care worker was assaulted and killed by two teens as he left his house of worship.
- BBC News: Youths jailed for barman killing
- BBC News: Feral pack who thrived on violence
- Sky News: Jail For Happy Slap Killers
- "Mænd sparkede tilfældig, mens politiet så det", Jyllands-Posten, May 11, 2006
- Turun Sanomat: Isosisko pisti kuoliaaksi pikkuveljensä hakkaajan Örebrossa
- The Age: DVD school in despair
- The Age: Teens face DVD porn charges
- BBC News: Life for 'happy slap' murder boy
- The Argus: Six teens bailed in 'happy slap' inquiry
- USA Today: Man urinates on dying woman, declaring it "YouTube material"