k, so here's the code to my first object right now, sorry about the mess :).

#local trn=3;
#local r=.25;

union{
 #while (trn>0)
  intersection{
   isosurface{
    function{
     f_helix1 (f_r(x,y,z)-3, f_th(x,y,z), y, 4, 4, .05,
      #if (trn=2)
       -atan(x/(abs(z)+.0000001))/(2*pi)+(.5*trn-r)
      #else
       atan(x/(abs(z)+.0000001))/(2*pi)+(.5*trn-r)
      #end
      , 2, 0, 0)
     - f_agate(x/2,y/2,z/2)*.01
    }
    contained_by{sphere{<0,0,0>,8}}
    #if(trn=1)
     max_gradient 15.0
    #end
    #if (trn=2)
     max_gradient 1.4
    #end
    #if(trn=3)
     max_gradient 3.4
    #end
    max_trace .01 all_intersections
    accuracy .00001
   }
   #if (trn=2)
    plane{-z,0}
   #else
    plane{z,0}
   #end
  }
  #local trn=trn-1;
 #end

 hollow
 pigment {Black}
 finish{
  Phong_Shiny
  reflection{,1}
 }
}

So if you're wondering what I'm trying to do, I've taken the spiral function
and changed it so it's a spiraled torus, but then I modded it again so that
as it wraps around the y-axis, it's minor radius decreases.  The result
looks similar to the MC Escher picture 'Spirals.'  I had to do it in 3
sections because of the nature of the function, so that's why theirs a
loop.  I thought that looked too flat so I subtracted some f_agate() from
it to give it some texture.  All the max_gradients are optimised for the
individual parts, and I added in the max_trace becase I was loosing the
visibility of some portions looking through it.  This is my first run with
the accuracy altered from default but that shadowing problem was evident in
the previous run (which took ~12hrs, picture below) despite being under a
reflective finish, I could still see the shadowing pixelation.

The end result is something that took several hours to render without the
finish on, I don't remember how many.  Right now I'm running it at high
radiosity settings on my dual P3 866MHz machine (2 threads, the image is
split into 2) and is just about pre-rendering @~12hrs.  And I'm sure it may
come up so here's my radiosity settings:
radiosity {
 pretrace_start 0.08
 pretrace_end   0.005
 count 400
 error_bound 0.1
 recursion_limit 1
}

Any thoughts?  I'll post an image when it finishes.

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