Hackers have revealed a button press code that allows access to a hidden, "special" options menu in Gran Turismo 5 Prologue that allows you to drive any car in the game and configure a number of other tweakables.

Mathieu Hervais, front man for the group that produced PSGroove, the open source version of PSJailbreak, revealed the code via Twitter.

Accessing the menu is simply a case of moving to the Miscellaneous section GT5 Prologue's option screen, holding down L1 and R1 and pressing down, right, right, down, right, right, down, right, right, down, right, right and pressing start. Pad movements needs to be done with the analogue stick, not the d-pad, in order to be recognised - and to be clear, the code only works in Prologue, not the full-on GT5.

Here's a quick video tour of what you see, along with a quick lap of the High Speed Ring in the unlocked Formula 1 Ferrari car.

While the prospect of a hidden menu suggests the promise of cool new modes not found in the game itself (as was the case with the 3D options we saw unlocked in the E3 demo for GT5), the reality of this menu is a touch more mundane.

It appears that the lion's share of the options are for configuring GT5 Prologue to set up specific cars and events for "Kiosk" use, that is for in-store and event demo purposes. However, by turning Kiosk mode on and making a single choice in the favourite cars section you are able to select and instantly race your chosen vehicle. This is a neat trick bearing in mind that the game has quite a large vehicles roster, and that accessing vehicles like the Ferrari F1 car involves a mammoth amount of grinding - the process of replaying the same races over and over again.

It's also possible to choose the exact selection of courses available and cars you'll be racing against. A server update feature also appears to be built in, but we couldn't get much joy from it - and indeed, using it actually caused our game to crash.

It's well worth taking a look at, and maybe with a bit more tweaking, players might be able to unearth some more functionality. However, bearing in mind the experimental nature of this, it's probably worth trying it out on a PSN sub-account so as not to put any legitimate save in any danger...