The spin-Hall effect - the influence of the intrinsic spin on the electron trajectory, which produces transverse deflection of the electrons, is a central tenet in the field of spintronics. Apparently, the handedness of the light's polarization (optical spin up/down) may provide an additional degree of freedom in nanoscale photonics. The direct observation of optical spin-Hall effect that appears when a wave carrying spin angular momentum interacts with plasmonic nanostructures is presented. The measurements verify the unified geometric phase, demonstrated by the observed spin-dependent deflection of the surface waves as well as spin-dependent enhanced transmission through coaxial nanoapertures even in rotationally symmetric structures. Moreover, spin-orbit interaction is demonstrated by use of inhomogeneous and anisotropic subwavelength dielectric structures. The observed effects inspire one to investigate other spin-based plasmonic effects and to propose a new generation of optical elements for nanophotonic applications.