Even the name sounds like it belongs to a sinister new adversary for Dr Who.
Introducing the Kilobots - obedient miniature robots that act together as a "swarm" to form a 1,000-strong army.
Scientists in the US created the soldier-like devices, each measuring a few centimetres across, to demonstrate how simple machines can display complex self-organising behaviour.
Given the electronic command: "Form a star shape", the Kilobots begin to blink infra-red signals to each other and arrange themselves into a five-pointed star. Or a 'K'.=:
They can be made to form many letters of the alphabet, using vibrations to slide across surfaces on three rigid pin-like legs.
The Kilobots' swarming ability can be compared with that of starlings flocking together in cloud-like "murmurations" or ants creating rafts and bridges with their bodies.
US lead scientist Professor Radhika Nagpal, from the Harvard School of Engineering and applied Sciences (HEAS) in Cambridge, Massachusetts, said: "The beauty of biological systems is that they are elegantly simple - and yet, in large numbers, accomplish the seemingly impossible.
"At some level you no longer even see the individuals; you just see the collective as an entity to itself."
The Kilobots, which resemble moving transistors, are given no direct information about their global position but collectively construct a co-ordinated system.
Each robot is equipped with infra-red sensors and two motors that cause their legs to vibrate.
Self-assembly begins with a tightly packed multitude of Kilobots programmed with a two-dimensional image of the target shape and a set of fixed fixed rules they have to follow.
Four "seed" robots start the process off, generating a domino-effect of signals that propagate through the rest of the swarm.
How each Kilobot positions itself depends on the distance between it and its neighbours. Robots become each other's reference points, building up an organised system from local interactions.
At every location, the Kilobots continually transmit messages via infra-red light signals showing their X and Y co-ordinates.
Results of the experiment are published in the journal Science.
Co-author and fellow HEAS scientist Dr Michael Rubenstein said living things operated in this way at every level. Single-celled amoebas joined together to create a "fruiting body" when food was scarce, while the co-ordinated colour change of individual cells helped a cuttlefish blend in with its surroundings.
He also cited the example of army ants linking bodies to form rafts and bridges that help them cross difficult terrain.
"Biological collectives involve enormous numbers of co-operating entities - whether you think of cells or insects or animals - that together accomplish a single task that is a magnitude beyond the scale of any individual," said Dr Rubenstein.
The research is another step in the development of artificially intelligent self-organising systems that will affect every day life in the future, say the scientists.
Prof Nagpal said: "Increasingly, we're going to see large numbers of robots working together, whether its hundreds of robots co-operating to achieve environmental clean up or a quick disaster response, or millions of self-driving cars on our highways. Understanding how to design 'good' systems at that scale will be critical."Suggest a correction