I just published a little experiment of mine—an idea for creating gradient effects using only two filament colors. By slicing the model into thin horizontal layers that gradually shift from one color to the other, you can create a smooth transition without needing actual gradient filament.

I first tried this with one of my Flexigrid models, and here’s an example applied to a vase. 

These are the vase colors I've tried. 

Translucent filaments work best since they let light through, allowing your eyes to naturally blend the colors. Let me know what you think. Is this something you'd like to be able to do to your own models?