The Sony PlayStation 3 is a very popular last-gen console, known for its large library and its weird architecture. Given that Sony has initially supported, and in fact even promoted Linux on the PlayStation 2 and PlayStation 3, this means that the consoles have a huge modding/hacking potential.
That is especially proven by the many hacks/jailbreaks available for the PlayStation 3, hacks which give the players more power over their console, allowing them to further customize it and install homebrew apps.
A brief history
Sony’s 3.55 update for the PlayStation 3 accidentally gave advanced users a way to find the (ECDSA) private key used by Sony to sign software, due to a failure of Sony’s ECDSA to generate a different random number for each signature. At first, the group responsible for discovering this did not leak the key, as the console was capable of running homebrew without it. Then, George Hotz, the man responsible for unlocking the iPhone, decided to publish the private key.
That is when a group of reverse engineers used the encrypted key with the 3.55 firmware in order to create their own custom firmware version, which gave users additional features. Thus, Rebug was created. With the help of Rebug and the private key, they were able to create their own features and software.
Upon seeing the huge following of Rebug, Sony added security measures to prevent creation of custom firmwares in their following updates, v3.56 and v3.60. However, users simply chose not to update, and games requiring a later firmware were quickly patched to run on v3.55. Soon after v3.60 was released, updates to the PlayStation Network were conducted to block any methods known that allowed PSN access on firmwares older than the latest official firmware, thereby blocking users who chose not to update.
Sony also filed lawsuits against both the group responsible for the initial discovery of the private key and against George Hotz. The lawsuit against George Hotz was resolved out of court, on the condition that George Hotz will never again resume any hacking on any Sony products.
What can it do now?
With Rebug, users nowadays have access to a wide range of tools with which to further customize their experience on their consoles. Such tools can be used to change your PlayStation ID in order to avoid online bans, or unlock trophies (this is just aesthetic, though, as going online with modified trophies will guarantee you a swift ban).
The main reason people use Rebug, though, is in to be able to run homebrew and pirated games on their consoles, thus saving a lot of players worldwide a lot of money. (New Age Soldier does not approve of piracy. If you like the games you’re playing, buy them!)
Sounds cool! How do I get it?
Here is a quick tutorial: