I remember seeing e-ink panel demos where the integrator claimed the usual slow refresh was a side effect of the low power requirements rather than a limitation of the panel. They claimed that a controller designed for fast refresh could show moving video on an e-ink panel. It kind of makes sense because you can address individual pixels in the panel and they can change state faster if you apply higher tensions. The trick is to refresh the whole panel at least 30 times per second.

You can also fool the human brain by rendering motion blur.