By means of electrochemical treatment, crystalline silicon can be permeated with tiny, nanostructured pores that entirely change the characteristics and properties of the material. One prominent example of this can be seen in the interaction of porous silicon with living cells, which can be totally unwilling to settle on smooth silicon surfaces but readily adhere to porous silicon, giving rise to great hopes for such future applications as programmable drug delivery or advanced, braincontrolled...