  I report the results of a series of works on the phase diagram of theories
with a different number of colors and/or quarks in a different representation
than in QCD. Similarities as well as differences as compared to the real world
are pointed out, focusing in particular on the interplay of confinement and
chiral symmetry breaking. It will be argued that recent lattice data may
provide us with a clue to understand deconfinement in cold dense quark matter.
