I use the latest ZBrush software to craft 3D nudibranch models. The organic way of modelling in ZBrush suits their crazy body shapes. I can also do all the preparation for 3D printing in ZBrush. It is then prepared for 3D printing prior to being uploaded to Shapeways where it will be 3D printed in White Strong and Flexible Nylon that gets a smooth polish to be ready for painting:
http://www.shapeways.com/shops/marulacreative
Polished Strong and Flexible Nylon ships in nine business days from Shapeways (faster options are available at extra cost). The material is intended for decorative purposes and is not suited as toys for kids. The material should not come into contact with heat or electricity. The nylon is not food safe. This material is not suitable for use in a fish tank. Products are printed in a layer by layer process, so sometimes these lines might be visible like a stepping effect. When they are polished it becomes less noticeable. See material here:
https://www.shapeways.com/materials/strong-and-flexible-plastic