With only two weeks left until game retailers everywhere are positively swamped in Halo 3 hysteria it comes as scant little surprise to see that the shameless whoring of Bungie’s final edition of the FPS sci-fi extravaganza has begun in earnest. Not that Xboxic is complaining, you understand, we’re drooling at the prospect of gunning with the Chief in glorious next-gen just as much as any other hype-inebriated fanboy. Bring it.

In this particular case, a post on Bungie’s official Web site has announced that alongside the usual sway of T-shirts, soft drinks, action figures and various other marketing deals designed to boost Halo 3’s public saturation, American retail titan Best Buy is offering everyone (yes, everyone) three full days of completely free (yes, free) Xbox Live Gold membership.

While those Xbox 360 owners with established full subscriptions won’t be bouncing off the walls after hearing of Best Buy’s generosity, Bungie notes that those armed only with a Silver subscription, or those who have “picked up a 360 just for Halo 3,” will get complete Gold access during the game’s launch period – Sept. 25, Sept. 26, and Sept. 27.

Although lucky upgrade recipients will gain temporary access to online co-op, multiplayer, Forge editing, and viewed Network Saved Films in Halo 3, the game’s File Sharing system will remain restricted to those players with a paid Xbox Live Gold membership, adds Bungie. Prospective Xbox 360 consumers still not swayed by the temptation of Halo 3 and three free Gold days on Live should also note that Best Buy’s offer opens Live to any game, not just Halo 3.

And, as if that wasn’t enough incentive, Best Buy is also presenting the Xbox Live and Best Buy Play & Win Sweepstakes, which will see a mighty 8000 Microsoft Points doled out to 144 randomly selected winners during the three-day free Gold membership period.

Wait, there’s more… the lucky 144 prize winners left scrambling to spend their Points on the Live Marketplace will also be entered into another prize draw where an impressive top-tier Samsung Home Theater system is up for grabs and (deep breath) an exclusive Halo 3 themed Pontiac G6 GXP Street Edition car.

Click HERE to register for the Xbox Live and Best Buy Play & Win Sweepstakes.