This is incredibly smart design. The Schnozzel Pumpbag, by camping gear manufacturer Exped, is about as simple, low-tech and lightweight as you can get. For campers with inflatable sleeping pads, you can either add weight to your kit by carrying an air pump, or you can inflate the thing with your lungs. If you go with the latter option, the moisture from your breath will fill the sleeping pad, which can lead to bacteria and mold.
The Schnozzel Pumpbag is a lightweight sack made of 70D ripstop nylon, and it allows you to quickly, easily inflate your sleeping pad without introducing any moisture. It's lighter than a conventional pump, and earns its keep twice as it can also be used as a compression sack to carry your sleeping bag.