I can see how the concept for the 'Halo suit' came about. A guy with some tinkering skills and an affinity for all things Xbox was watching pessimistic reports of the latest worldwide conflicts on TV. And he thought to himself: The Master Chief could solve this thing with one snap of his cybernetically-enhanced fingers.
So he got to work. He spent two years building an authentic, working Halo suit that he's hoping will eventually be used by soldiers in Iraq and Afghanistan. It's no Halloween costume. The $15,000 armor can protect against knives, bullets, and bombs; and it's equipped with everything from a laser pointer to holsters to pepper spray to a solar-powered air circulation system. According to BornRich, he's hoping that mass-production of the Halo suit will bring its cost down to about $2,000.
Side note: I didn't know the Master Chief carried pepper spray.