Lizard Squad was responsible for DDoS attacks on PlayStation Network and Xbox Live

The hacking group has released the ‘LizardStresser’ DDoS tool to help people overload websites and internet services, charging between $6 and $500 per attack

http://www.theguardian.com/technology/2014/dec/31/lizard-squad-ddos-service-playstation-xbox-lizardstresser