We've covered Neri Oxman before, but we wanted to spotlight her work given her recent addition to the faculty at MIT's Media Lab. The amazing thing about Oxman's work is that its appearance seems so biological and organic, yet every piece is fabricated from machines and man-made technologies. These first two objects, for instance, are 3D-printed acrylic composites using the Connex500, allowing Oxman to print multiple materials at once and recreate "veins."
Having seen these two CNC-ed pieces in person, I can say they are absolutely mind-blowing. The metal one has intricately carved topological-like regions, which apparently represent the stress loads in tissue. The acrylic one interacts with light so wonderfully and playfully, you might never realize it's based on the process of mineralization.
See also: Nervous System's "Hyphae" Lamp