The Lizard Squad sounds like the latest line of toys you'd see advertised on a kids' TV show. Unfortunately, it's something far more dangerous.
In reality, the Lizard Squad is the newest high-profile group of hackers to make a mark. It was behind the Sony and Microsoft gaming network outages that happened over Christmas. Surprisingly, though, shutting down Sony and Microsoft wasn't the goal of the attack.
The actual goal of the attack was to be an advertisement for the Lizard Stresser. This tool lets non-hackers pay a fee to knock a chosen website offline. The Sony and Microsoft takedown was Lizard Squad proving to the world that the service works.
Even more worrying that rent-a-hacking services, though, is how Lizard Squad is able to launch its attacks. In fact, it's possible something in your home was part of it, and I don't mean your computer.