Is there anyway to weave 3D objects in with a GUI?

I'm looking to use a backdrop then 3d objects then the rest of the GUI.

 

The new GUI stuff introduced in 2.0 always draws on top of the objects in your scene so what you seek isn't possible with the GUI features alone. Instead you might consider using one camera that is rendering only the backdrop (a flat plane surface) then the normal game camera rendering after that (on top) so you get the layering you seek.

 

Thanks again

 

If you have pro, you can render to texture also

 

You could also attach an old GUI element to the background camera (and have it do nothing but clear the image buffer) -- I don't know if that's a "cheaper" way to render an element, but I suspect it is.