This is a collection of all of the marble run pieces I put together. Feel free to remix, etc. I drew them in Sketchup, and exported with a plugin. All of them have been checked with Netfabb, and ready to print.

I used Sketchup to draw these, and have included the Sketchup file for the configuration I drew. I would suggest printing at 0.5 scale. The blue fork image was printed at 0.5 scale, and the yellow snake piece was printed at 0.3 scale. Make sure to enable support. I used 15%, but 10% would likely be fine.