People dressing up as game characters isn't anything new. There's an entire cosplay scene centered around that. What is new, though, is how good these two guys look in their homemade costumes.

"This is Adam and Walter, from the 405th. Hi Adam and Walter! Adam and Walter like Halo, and they like cosplay, so seeing them dressed as Halo characters isn't that big a shock. What is a shock is the quality of these costumes! If somebody told me these were photos smuggled off the set of the Halo movie I'd totally agree with them, for a second, before remembering there is no Halo movie, then saying "aaaahhhh, ya got me". (Kotaku)