Refreshments are served at 3:30 p.m. in Physics room 242In this talk I will give a brief overview of several projects which explore different facets of electron interactions in mesoscopic systems. I will start from the discussion of magnetic materials where microscopic spin-orbit interactions - a relativistic correction to electron spectrum which connects spin and orbital degree of freedom - allow us to control macroscopic properties, such as magnetization direction. In high mobility 2D gases subject to high magnetic fields interaction effects lead to the formation of a variety of correlated states, such as fractional quantum Hall effects, Wigner crystal and, possibly, states with non-Abelian excitations. By introducing uniaxial strain we are able to induce anisotropy of exchange interaction and resolve an outstanding problem related to the orientation of anisotropic "stripe" phases, as well as to elucidate a microscopic origin of "bubble" phases in quantum Hall regime. Finally, I will discuss our latest work where a combination of low dimensionality, strong spin-orbit interaction and superconducting coupling lead to the formation of an entirely new state of matter which supports excitations with non-Abelian statistics. These exotic excitations have properties of particles proposed by E. Majorana almost 80 years ago.