  We construct the most general supersymmetric configuration of D2-branes and
D6-branes on a 6-torus. It contains arbitrary numbers of branes at relative
U(3) angles. The corresponding supergravity solutions are constructed and
expressed in a remarkably simple form, using the complex geometry of the
compact space. The spacetime supersymmetry of the configuration is verified
explicitly, by solution of the Killing spinor equations. Our configurations can
be interpreted as a 16-parameter family of regular extremal black holes in four
dimensions. Their entropy is interpreted microscopically by counting the
degeneracy of bound states of D-branes. Our result agrees in detail with the
prediction for the degeneracy of BPS states in terms of the quartic invariant
of the E(7,7) duality group.
