JoeBlow Fat pump!
Topeak's JoeBlow Fat is the first floor pump exclusively designed for low pressure fat tire bikes. The massive over-sized barrel is 1.5 times larger than standard floor pumps and delivers big air volume to fill fat tire bikes quickly. Low pressure gauge (up to 30psi) with pressure release button on the hose head lets you adjust tire pressure accurately.
I tested this bad boy out myself last night, pumping up one of my fat bike tires from completely flat to 10psi. With my Giant Control Tower 2 pump (a very fine and capable pump in its own right), it took me about 1 minute and 85 pump strokes. With the JoeBlow Fat pump, it took me only 45 seconds and 45 pump strokes!
The built-in air gauge on the JoeBlow Fat pump has markings in half-pound increments starting at 2-1/2 psi, making it easier than ever to dial in those low pressures for snow bike riding.