We study orbifolds of N=4 U(n) super-Yang-Mills theory given by
discrete subgroups of SU(2) and SU(3). We have reached many interesting
observations that have graph-theoretic interpretations. For the subgroups of
SU(2), we have shown how the matter content agrees with current quiver theories
and have offered a possible explanation. In the case of SU(3) we have
constructed a catalogue of candidates for finite (chiral) N=1
theories, giving the gauge group and matter content. Finally, we conjecture a
McKay-type correspondence for Gorenstein singularities in dimension 3 with
modular invariants of WZW conformal models. This implies a connection between a
class of finite N=1 supersymmetric gauge theories in four dimensions
and the classification of affine SU(3) modular invariant partition functions in
two dimensions.Comment: 28 pages, 5 figs, 1 ref added, 1 table updated and some comments on
binary dihedral groups adde