We have systematically constructed a set of stable silicon nanocluster families with large arbitrary fullerene-type hollows inside. In addition, conglomerate structures are designed by connecting the nanoclusters through pentagonal and hexagonal junctions. The atomic and electronic structure of the proposed objects is investigated using the semiempirical quantum-mechanical method. It is shown that within each family the band gap and the stability are inversely proportional to the particle effective size. The clusters inherit a wide variety of structural and symmetry properties from their parent silicon fullerenes. The conglomerates confine electrons like quasi-molecules with a peculiar electronic structure related to the junctions. Quantum dots and their conglomerates can host guest atoms in their hollows and therefore present a new promising type of nanomaterials with tunable electronic properties.