Jennifer's Figure-Eights:

This space curve was produced using the following Maple commands:

> x:=2*sin(t)*cos(t);
> y:=sin(t);
> z:=t;

                         x := 2 cos(t) sin(t)


                             y := sin(t)


                                z := t

> spacecurve([x,y,z],t=0..10*Pi,numpoints=1000,
>   thickness=2);