The cosmic microwave background (CMB), the relic radiation left over from the Big Bang, has been a cornerstone of our cosmological model of the Universe for more than 50 years. Observations and analysis of the CMB tell us the composition of the Universe and have been crucial for understanding the existence of dark matter and dark energy. I will present an overview of the rich scientific questions currently being pursued by CMB experiments, which ties together the most disparate scales possible in science: quantum mechanics and cosmology; the beginning of the universe to the present day. I will discuss astrophysics being done with CMB surveys, including followup studies of high-redshift galaxy evolution with the Atacama Large millimeter/submillimeter Array (ALMA) and the James Webb Space Telescope (JWST) and the nascent field of mm-wave time-domain surveys. I will conclude by describing current efforts in line intensity mapping (LIM), including a description of the Terahertz Intensity Mapper (TIM), and the prospect for the future.