How can I speed up Freestyle rendering? I'm rendering shapes in Freestyle.  Nothing fancy (think flowerpots).  I want a white object and white background, and of course black Freestyle outlines.  No textures.

It's working fine, but I wonder if there's a faster way to do the renders.  Since my planned output is so basic, is there a way for me to - I don't know - turn raytracing off, or use less of it, or turn off other options or features so the rendering routine has fewer things to do and takes less time?

Right now, I have no lamps in my scene; im the World tab, I'm using a white horizon color and environment lighting with energy level 10.
Disable everything else

As you thought, ther are lots of things you can avoid to render if you are looking for just the freestyle edges.

You just have to disable all the elements you can find in the Include section of the Layer panel you can find in the Render Layers tab (except Freestyle obiuvsly, if you are using Blender Render)