Using Convergent Technology, it's easy to make some very interesting shapes defined by implicit surfaces. There's a presentation (movie and PDF file) on this topic here. There are applications in industrial design and 3D printing.
The code below was used to create the models shown in the presentation.
pretty cool stuff!
Production: NX10.0.3.5 MP16/TC11.2
I'd rather be e-steamed than e-diseaseled