If you're a fan of Halo 4, then you might be interested in Forward Unto Dawn, a live-action series which premiers a month before the game's release for the Xbox 360.
Master Chief isn't the main star of the show, but he happens be o in it, and you can see what he looks like above in his MJOLNIR Powered Assault Armor, which has been reproduced for the series.
Despite the fact that it is probably made of polystyrene and fiberglass, the armor looks pretty damn real.
Halo 4 comes out for the Xbox 360 on November 6, 2012 and is the first title in a new trilogy of Halo titles revolving around the Forerunners, who serve as the Master Chief's enemies this time around. It is set to offer both a huge single player campaign and an expansive multiplayer co-op campaign, in addition to competitive modes.