The Minds Eye BézierCurve Xtra contains a set of Lingo
functions for generating Bézier curve points for drawing or
animating. You can draw pre-defined or random curves in realtime or
you can set a sprite animation to follow Bézier positions
along a curve.
It also works in 3D! You can create 3D Bézier Curves or
you can animate a 3D object travelling along a Bézier path
(see the example Director movie in the full evaluation bundle)