The structure functions of deep-inelastic scattering receive, among
others, contributions from massive quarks like the charm and bottom
quarks. In the limit where the virtuality Q^2 is much larger than the
heavy quark mass m^2 the heavy flavor Wilson coefficients have been
shown to factorize into massless Wilson coefficients and massive
operator matrix elements. This factorization allows for an analytic
calculation of the 3-loop QCD corrections by calculating the 3-loop
massive operator matrix elements. We report on recent progress in this
endeavor and present some applications of the results obtained so far to
the structure functions F_2, g_1 and xF_3, as well as to the
Gross-Llewellyn-Smith and the polarized Bjorken sum rules. Finally we
also touch upon applications of our results to anomalous dimensions and
the variable flavor number scheme for parton distributions.