Nanoscience today enables many fascinating low-dimensional structures and new materials with previously inaccessible properties. Nanostructures with mechanical degrees of freedom offer compelling characteristics that make them interesting for both fundamental studies and technological applications. This talk will describe my collaborative research efforts in exploring vibrating nanowires, and in engineering these very thin nanowires into functional and high-performance nanoscale electromechanical systems (NEMS). I will show NEMS resonators operating in the very-high and ultra-high frequency (VHF/UHF, 30MHz – 3GHz) ranges, based on silicon nanowires enabled by a hybrid bottom-up/top-down process. Exploiting the interesting properties of thin silicon nanowires, we have developed an all-electronic, on-chip VHF/UHF signal transduction for such devices. This opens up the opportunities for monolithic integration of NEMS with electronics, and for self-sensing nanowire NEMS that can be manufactured by industrial SOI technology. I will then report on latest progress in realizing very large scale integration (VLSI) of Si nanowire NEMS with Si nanowire transistors by using industrial foundry capability, along with their emerging applications in sensing and signal processing.