  We review recent progress in applying the AdS/CFT correspondence to
finite-temperature field theory. In particular, we show how the hydrodynamic
behavior of field theory is reflected in the low-momentum limit of correlation
functions computed through a real-time AdS/CFT prescription, which we
formulate. We also show how the hydrodynamic modes in field theory correspond
to the low-lying quasinormal modes of the AdS black p-brane metric. We provide
a proof of the universality of the viscosity/entropy ratio within a class of
theories with gravity duals and formulate a viscosity bound conjecture.
Possible implications for real systems are mentioned.
