Ah! Happens to me sometimes. I'll go around a corner and suddenly no power. The gas sloshes to one side of the tank and when fuel's low there's actually nothing under the pump for a moment and it pumps nothing (til you straighten out and gas sloshes back down).
More so on right turns then left it seems; must be the shape of the tank or the pump's installed slightly off-centre. Were you below 1/4 tank when that happened?