The pea-sized mini-brains developed by Austrian scientists have not yet developed evil psychic powers - the goal is more to test treatments on them.
They used either embryonic stem cells or adult skin cells to produce the part of an embryo that develops into the brain and spinal cord - the neuroectoderm.
This was placed in tiny droplets of gel to give a scaffold for the tissue to grow and was placed into a spinning bioreactor, a nutrient bath that supplies nutrients and oxygen.
The cells were able to grow and organise themselves into separate regions of the brain, such as the cerebral cortex, the retina, and, rarely, an early hippocampus, which would be heavily involved in memory in a fully developed adult brain.
The brains are described as being akin to those of a nine-week-old fetus, but incapable of thought. Nonetheless, one of them did attempt to donate money to Uwe Boll's Kickstarter.
I might have made some of that up.