While there are various ways of stowing a compact tire pump within a bicycle, a full-size model is almost always going to make the pumping easier. Frame-fit hand pumps are certainly one way to go, but inventor Alexander Haager has created something stealthier – his AirSupply pump doubles as a seatpost.
To use the device, you just pull its coiled air hose out of a built-in under-saddle pack, attach that hose to the valve stem of the front or rear tire, release the AirSupply's locking collar, then start pumping the seat up and down by hand. It works with Schrader or Presta valves, and comes with adapters which allow it to fit in any diameter of seat tube.
The AirSupply also has an integrated pressure gauge, a built-in LED tail light (in the pack), and is designed to easily reach a maximum tire pressure of 116 psi (8 bar). It's made from forged 6061 and 7075 aluminum, tipping the scales at 480 g (16.9 oz) – keep in mind that some of that weight would replace that of an existing conventional seatpost.
It is worth noting that the presence of the hose pack would make it rather difficult to also mount a cargo-carrying saddle pack.
Additionally, although the AirSupply is being touted as "The World's First Air Pump in Your Bicycle," it isn't. BioLogic's PostPump 2.0 pulls completely out of the seat tube, so it can be set on the ground and used as a floor pump.
Nonetheless, if the AirSupply concept is more appealing to you, you can currently support its production on Kickstarter. A pledge of US$40 will get you one, if all goes according to plans.