  We identify potentially the world's most sensitive location to search for
millicharged particles in the 10 MeV to 100 GeV mass range: the forward region
at the LHC. We propose constructing a scintillator-based experiment, FORward
MicrOcharge SeArch (FORMOSA) in this location, and estimate the corresponding
sensitivity projection. We show that FORMOSA can discover millicharged
particles in a large and unexplored parameter space, and study strongly
interacting dark matter that cannot be detected by ground-based
direct-detection experiments. The newly proposed LHC Forward Physics Facility
(FPF) provides an ideal structure to host the full FORMOSA experiment.
