This Fractal Cellular procedural texture has been rendered into a volume data cube. It is a non-tiling 8-bit texture at 256 x 256 x 256 voxel resolution. Iso-surface meshes are also provided in PLY and STL. I have also included PNG codec AVI versions, one of which "fades" at the edges (for making surfaces that don't end abruptly).
These textures are from an archive I made nearly a decade ago, by simply sweeping a plane through a procedural texture and rendering out the results. Here are the available formats:

RAW data 256x256x256 8-bit (zipped), 16MB uncompressed

BMP sequence 256x256x256 8-bit (zipped), 17MB uncompressed

PNG codec AVI 256x256x256

PNG codec AVI 256x256x256 (faded 16vx at edges)

PLY isosurface mesh 1.6M polygons

STL isosurface mesh (reduced) 810K polygons

This is from my series of volumetric objects created to help people explore the differences between polygonal and volumetric representations of objects.

Learn more about the benefits of volume-based data structures for 3D printing here:

40westdesigns.com/blog/?p=371

Read more on the subject in my post on Engineering.com here:

engineering.com/3DPrinting/3DPrintingArticles/ArticleID/4523/2012-The-Beginning-of-the-End-for-Polygons.aspx