Robert's Bow Tie:

This space curve was produced using the following Maple commands:

> x:=(10+t^2)*cos(10*t);
> y:=(10+t^2)*sin(10*t);
> z:=t+3*sin(50*t);

                                   2
                       x := (10 + t ) cos(10 t)


                                   2
                       y := (10 + t ) sin(10 t)


                         z := t + 3 sin(50 t)

> with(plots):
> spacecurve([x,y,z],t=-4*Pi..4*Pi,numpoints=5000,
>   axes='NORMAL',orientation=[40,60]);