You may have seen some very small cameras in your day, but nothing like this. University of Stuttgart scientist have developed a 3D-printed, three-lens camera that's just 100 micrometers (0.004 inches) across. That's small enough that you could inject into your body with a syringe -- perfect for endoscopy and other times you'd want to observe a patient's body from the inside. It currently needs to be tethered to an optical fiber, but it can focus on objects as close as 0.12 inches. You can even print unconventional lens shapes (such as rings or triangles) to fit specific shapes and goals.