The CMB power spectrum is a cornerstone of the LCDM cosmological model. Current and future CMB datasets are providing even richer information, as the CMB provides a well-understood backlight for probing the large-scale structure after recombination. I will discuss the use of CMB lensing and the kSZ effect to constrain cosmology and reionization, using data from the Atacama Cosmology Telescope.
DAA