thanks for the answer Mark. yeah I basically have been trying that and I at least have gotten the rotation working, using tangent constraint.

I actually saw something to that effect in your book with the helic particles around a curve. Great Book by the way, very helpful.

It works perfectly on a two dimensional curve, say in th xz plane, but when pulling up a point in the positive y direction it will cause the object to point outward(say down the z-axis, if the curve was made in the z direction).

-Is there anyway to force the object(say a cone) to remain pointing downward(down the y axis)?

thanks again,
Nic