Mercury has awakened interest as a potential material for spallation neutron source targets. Institute of Physics, University of Latvia has a 30 years experience of investigations in mercury. As specially projected building includes a 350 m(2) experimental hall. The largest loop, containing 5 x 10(3) kg of Hg, can be transferred for solution of different tasks. As the first example results are presented when integral developed pressure and local (distribution of void fraction) characteristics of a two-phase mercury/gas riser were investigated. Second example - investigation of velocity fields and heat transfer conditions close to the beam entrance window in the SINQ target thermohydraulic mockup. Third example was selected to illustrate the diversity of tasks. Heat transfer from wetted and non-wetted walls was compared. The flow was homogenized by means of an orthogonal to the walls magnetic fields.