MACN member /u/NeilSawhney has some pretty great 3D printing projects that I've got to share!
First, take a look at this ring he modeled based on a metal design by Kinekt Design. It was printed through Shapeways on an industrial machine that can achieve a much finer resolution than your average FDM machine. You can find a video of the ring in action on this website Neil put together.
Neil also made some great candle molds, including this Make Anything candle! He forgot to mirror the text on the mold, but that's how you learn (I've made the very same mistake with T-shirt iron-ons)!
Keep up the great work Neil, and thanks for sharing!