Many games have glitches where you keep wondering why they even exist, why they haven't been caught by the developers and so on, but this one found in the PS3/360 version of Diablo 3 is outright absurd, for two reasons: the PC version has been out for almost a year and a half and it never existed there (even though I'm fully aware you can't just copypaste a PC game on a console), and it works on one specific bonus on a particular set of items and ABSOLUTELY NOWHERE ELSE.
The idea behind the glitch is that when you equip two items of the Blackthorne set, you gain a boost of 100 vitality (which represents a rather substantial 3500 HP at level 60, which you have to be to equip these items), and keep these points as long as you have two items from that set equipped. The moment you have less than two, you lose these 100 points. (You probably already know how that kind of thing works, but I just want to make sure.) Well, what this glitch does is that whenever you log out, these 100 vitality points become a PERMANENT boost. You can then log back in, at which point you get another temporary 100 vitality boost that then becomes permanent when you log out, and so on and so on.
For reference purposes, since I'm aware most people here have never played this, your typical character will usually end up in the ballpark of 30000-60000 HP. So yeah, pretty freaking gamebreaking glitch there.