large-scale multiscale modeling and simulation

There have been several discussions on "Extreme Mechanics" in recent weeks and I would like to extend this topic to "Extreme Computing". As we develop materials that are more complex, hierarchical and are spanning multiple spatial scales, we will need computational tools that can describe them well. Fluid dynamics community has long time ago embraced large-scale computing of conservation laws of mass, momentum and energy. In mechanics of materials, large-scale computing is still in infancy.