A group of console hackers called Fail0verflow have managed to create the world's first low-level hack of the Sony PlayStation 4. Until now, no one has been able to install a custom operating system on the PS4.
The group disclosed in a YouTube video that they were able to break the console's security measures and compile a custom version of Linux for use on the console, which they have since made publicly available on their website. This version of Linux is capable of running a variety of apps, including games. The group demonstrates its capabilities by running a modded version of Pokemon Emerald, which they've renamed "Pokemon PlayStation Version."
The outfit is well known for its previous console hacks. They previously managed to hack the PlayStation 3, Nintendo Wii and Wii U.
Whether the hack will allow software pirates to exploit the system and share pirated games remains to be seen. For now, you can't really do much with it.