  The lecture is a brief review of the following topics: (i) collective flow
phenomena in heavy ion collisions. The data from RHIC indicate robust
collective flows, well described by hydrodynamics with expected Equation of
State. The transport properties turned out to be unexpected, with very small
viscosity;
  (ii) physics of highly excited matter produced in heavy ion collisions at
T_c<T<4T_c is different from weakly coupled quark-gluon plasma because of
relatively strong coupling generating bound states of quasiparticles;
  (iii) wider discussion of other ``strongly coupled systems'' including
strongly coupled supersymmetric theories studied via Maldacena duality, as well
as recent progress in trapped atoms with very large scattering length.
