Pocket bellows was invented by John D. McCann, however as with many things there are people who said they were using them for years before the internet was around. Basically a Pocket Bellows is a collapsible tube that you blow through into your fire or coals. It allows you to keep a safe distance from the fire so you don't inhale smoke or set your hair on fire. Some basics, the bigger the tube the more air you can move so I say go big or go home.
Some videos on the DIY approach
Some videos on the DIY approach