Over the last century, light sources – in particularly, lasers – have improved exponentially, transforming our understanding of the universe from the large to the small and revolutionizing industries from medicine to semiconductors. Presented here is a glimpse into research with the world’s most powerful lasers, ranging from Petawatt-scale solid-state lasers to accelerator-based free-electron lasers (FELs). Such lasers can excite and probe matter in extreme conditions, enabling the study of exotic astrophysical phenomena, such as nuclear fusion, in a laboratory setting. Light sources are critical for powering semiconductor lithography, which is the key driver of Moore’s Law. Over the decades, lithography light sources have evolved from simple mercury lamps to UV lasers to modern plasma-based extreme ultraviolet (EUV) sources. Future accelerator-based EUV sources – such as EUV-FELs under development at my startup xLight – offer 10x less energy consumption, 4x more power, and more lithography control than plasma-based EUV sources. These sources can economically power Moore’s Law for decades to come and offer a bright future for the semiconductor industry and the growth of AI.