Biological events (e.g., immune responses and infection by disease) originate from the interactions that take place between individual molecules at the nanoscale. Probing single-molecule dynamics is therefore a powerful method for understanding the underlying mechanisms of biology. Furthermore, because of the great complexity of biological systems and the rapid motion of single molecules, measurements with high spatial and temporal resolution are highly desired. In biological membranes, for example, the ability to track a single molecule down to the nanoscale within microseconds would enable investigations into the existence and functions of putative membrane nano-domains with molecular clarity. High-speed measurements are generally noisy, however, as a result of the limited signal-integration time as well as the introduction of electronic noise. These issues prevent close examination of nanoscopic dynamics at the single-molecule level.