This is so called persistence of vision when the perceptual processes of the retina of the human eye retains an image for a brief moment. Such inertia causes an illusion of motion rather separate frames displayed in quick succession. So this illusion technique can be used in many areas. Probably you are avare about rotating clock projects so why not to put similar technique in bicycle tire and look cool in the dark.

Raphaël Assénat have been developing a rotating LED bar on bicycle wheel for quite long time and came up with several versions of project. The newest is capable to read RPM of wheel and display value with LEDs. Also Display scan rate is fixed what allows to display smoothly at any rotating speed.