In the advent of commercialization of inorganic nanotubes (INTs), new routes are proposed for tailoring the properties of polymer nanocomposite systems. INTs differ from multi wall carbon nanotubes (CNTs) with respect to its diameter (80nm compared to 10nm) and length (1 micron compared to a few microns). Distinctively, pristine INTs surface are rich in sulfur and tungsten elements with a small fraction of oxygen. CNTs surface is composed aromatic moieties that lead to agglomeration. The surface properties of these two classes of nanotubes effect their rheological properties and dispersion in polymers. The viscosities of CNTs containing resins (Epoxies, Polyurethanes) or melts (Polypropylenes, polyamides) are significantly higher compared to the respective neat polymers, while INTs demonstrate good dispersion in polymers and decrease the nanocomposite viscosities compared to the neat polymers. The reduced viscosities open new opportunities for INTs in liquid based processes like RTM (resin transfer molding) where the viscosity is of utmost importance. The good dispersability of INTs leads to improved mechanical as well as thermal properties. The mechanical properties of nanocomposites containing less than 1% by weight of INTs increase the modulus by more than 50% for epoxy and polyurethane systems and toughness by more than 70%. At the same concentrations CNTs polymer systems showed an increase by only 30% in modulus and 20% in toughness. Simultaneously the glass transition temperature of INTs containing polymers showed a significant increase (more than 15oC) while equivalent CNTs containing polymers showed an increase of only a few degrees. SEM micrographs supported the experimental results indicating very good dispersion of the INTs and unique fracture mechanisms like crack bowing and cavitation. The outstanding attributes of INTs containing polymers compared to CNTs nanocomposites, comprise the basis for industrial applications.