Small scale, self sustaining nano-fabrication will facilitate technological and economic independence, as the entire industrial basis of society can become mobile and robust in the face of catastrophic damage.
For self replicating fabrication schemes, creation of computational media is a limiting step. Do-it-yourself fabrication of computational media is one of the major barriers to shrinking the size and energy requirements of an industrial basis for society. ( Furthermore, if we are to colonize off-world, we will need to be able to build a self-sustaining hight tech fabrication facility that can fit inside a shipping container ). To this end, solving the do-it-yourself nanofabrication problem will be one of the most interesting developments of the coming century.
Also, I really should get off this futurism bent and and do some real research.