  We study the externally-driven motion of the domain walls (DWs)of the pi/2
type in (in-the-plane ordered) nanostripes of the crystalline cubic anisotropy.
Such DWs are much narrower than the transverse and vortex pi DWs of the
soft-magnetic nanostripes while propagating much faster, thus, enabling dense
packing of magnetization domains and high speed processing of the many domain
states. The viscous current-driven motion of the DW with the velocity above
1000m/s under the electric current of the density 10^12A/m2 is predicted to
take place in the nanostripes of the magnetite. Also, the viscous motion with
the velocity above 700m/s can be driven by the magnetic field according to our
solution to a 1D analytical model and the micromagnetc simulations. Such huge
velocities are achievable in the nanostripes of very small cross-sections (only
100nm width and 10nm thickness). The fully stress driven propagation of the DW
in the nanostripes of cubic magnetostrictive materials is predicted as well.
The strength of the DW pinning to the stripe notches and the thermal stability
of the magnetization during the current flow are addressed.
