Fire safety experts will tell you that most of the deaths in a fire are due to smoke inhalation, and not from getting caught in the flames. Many indoor fires generate a thick choking poisonous smoke that can quickly knock you unconscious. Therefore, to escape with your life, it's important that you can breathe as you escape.
Looking suspiciously a hijacked McDonald's french fry pouch, the Firescuba pops open to form a cup that you hold over your mouth and nose, so that the air you breathe in is drawn through a carbon filter. This is similar in many ways to a smoke hood, but with the advantage that it's small enough to carry with you all the time. Even the best smoke hood isn't much help if it's sitting in a drawer at home when you get caught in a conflagration. With a Firescuba in your pocket or bag, it might just give you enough time to reach fresh air.
The Firescuba is just a concept right now, but assuming it works as advertised, this seems like a great idea.