A growing number of commercial and enterprise systems rely on compute and power intensive tasks. While the demand of these tasks is growing, the performance benefits from general-purpose platforms are diminishing. Without continuous performance improvements, grand-challenge applications, such as computer vision, machine learning, and big data analytics may stay out of reach due to their need for significantly higher compute capacity. To address these convoluted challenges, there is a need to move beyond traditional techniques and explore unconventional paradigms in computing. This thesis leverages approximate computing---one of the unconventional yet promising paradigms in computing---to mitigate these challenges and enable the traditional ...