It’s been a while since Halo 3 first saw daylight, in September 2007, and made Bungie Studios the proud owner of 2007’s best selling game.

Now Bungie prepares a little present for Halo 3 gamers for “Bungie Day” (July 7) and offers them the “Cold Storage” map and a set of other goodies free of charge.

The new map will bring back memories for first Halo players, as it is in fact a remake of the “Chill Out” map. “Cold Storage" can be downloaded for free, together with game pics and a Bungie Day Xbox 360 dashboard theme, all for free.

And that’s not all, as the Legendary Map Pack released this April will now be just 600 Microsoft points from 800 Microsoft Points ($10).

Released on September 25, Halo 3 brought its developers more than $170 million in the first day of availability, surpassing by far its predecessor (Halo 2, with “only” $125 million) and Spiderman 3 ($67 million).

In terms of sales, the 2007 performance was forgotten once Grand Theft Auto IV came out. The game exceeded all expectations and managed to surpass all day-one and week-one sales records: 3.6 million units sold in the opening day alone, worth $310 million, 6 million units within a week, worth $500 million.

The action of the Halo 3 game revolves around Master Chief, a genetically altered, cybernetically enhanced Spartan supersoldier, who must race back to Earth to stop the Covenant, a fictional militaristic alliance of alien races, first introduced in the original Halo game.