  Angular momentum of spinning bodies leads to their remarkable interactions
with fields, waves, fluids, and solids. Orbiting celestial bodies, balls in
sports, liquid droplets above a hot plate, nanoparticles in optical fields, and
spinning quantum particles exhibit nontrivial rotational dynamics. Here, we
report self-guided propulsion of magnetic fast-spinning particles on a liquid
surface in the presence of a solid boundary. Above some critical spinning
frequency (higher rotational Reynolds numbers), such particles generate
localized 3D vortices and form composite 'spinner-vortex' quasi-particles with
nontrivial, yet robust dynamics. Such spinner-vortices are attracted and
dynamically trapped near the boundaries, propagating along the wall of any
shape similarly to 'liquid wheels'. The propulsion velocity and the distance to
the wall are controlled by the angular velocity of the spinner via the balance
between the Magnus and wall-repulsion forces. Our results offer a new type of
surface vehicles and provide a powerful tool to manipulate spinning objects in
fluids.
