Shaken, not stirred -- mythical god's capsules please!

Everything depends on how you look at them. Looking from one side you will see one face; and when looking from the opposite side -- you will see a different one. So appear Janus capsules, miniature, hollow structures, in different fragments composed of different micro- and nanoparticles. Theoreticians were able to design models of such capsules, but a real challenge was to produce them. Now, Janus capsules can be produced easily and at low cost.