  We used a thermodynamic integration scheme, which is specifically designed
for disordered systems, to compute the interfacial free energy of the
solid-liquid interface in the hard-sphere model. We separated the bulk
contribution to the total free energy from the interface contribution,
performed a finite-size scaling analysis and obtained for the (100)-interface
$\gamma=0.591(11)k_{B}T\sigma^{-2}$.
