  A key property of many BPS solutions of supergravity is the fact that certain
probe branes placed in these solutions feel no force, essentially because
electric repulsion and gravitational attraction balance one another. In this
letter we show that the existence of brane probes that feel no force is also a
property of many non-supersymmetric, non-extremal solutions of supergravity.
This observation requires a new class of brane probes that move with constant
velocity along one or several internal directions of the solution but the
zero-force condition that makes the branes "float along" at constant speed, or
soar, requires the velocity to be purely imaginary. While these probes are not
physical, their no-force condition implies the existence of hidden relations
between the warp factors and electric potentials of non-extremal solutions in
certain duality frames, and this provides insight into the structure of such
solutions and can greatly simplify the search for them.
