A novel mechanism of the drift of a gas is described. It occurs under velocity-selective excitation in a cell with magnetized walls. The effect can be used for isotope-selective control of the spatial distributions of gases and purification, probing the corrugation of the near-the-surface potential for the gas-surface atomic scattering, studying heterogeneous chemical reactions, and potentially in laser cooling. (C) 2003 Elsevier B.V. All rights reserved.