After three years in development, Bungie finally released Halo 3 for the Xbox 360.

Microsoft marketed Halo 3 like crazy and even had Bill Gates at the launch event at a Best Buy in Bellevue, Washington, to hand out the first official copy. All that hard work paid off, as Halo 3 broke the record for the highest gross sales of a video game within 24 hours of release with $170 million.

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