Today, parallel programming is easy and parallel computing is available for the masses. Distributed memory parallel computers such as Beowulf clusters and massively parallel supercomputers require a suitable splitting of the data, with good load balance and minimal communication. In this talk, we present new ways of splitting data, in the context of two applications: - Construction of low-energy atomic configurations of amorphous silicon, with up to 20,000 atoms, used as input to simulate e.g. solar cells. This 3D computation is based on simulated annealing, with phases of local relaxation, global relaxation, and information exchange. The particle data are split based on sphere packing lattices. - Latent semantic indexing, a method used in search engines. This requires the iterative solution of large sparse SVD problems. A new non-Cartesian method is presented for the distribution of sparse matrices for such computations.