VPixx Technologies, a company in Canada that makes equipment for vision researchers, has developed PROPixx, a projector capable of a 500Hz native refresh rate!
This is a native refresh rate, without interpolation. It is one of the highest native refresh rates available on the market for a display.
They also make VIEWPixx, a 1920×1200 120Hz LCD monitor with 12-bit color and scanning backlight.