I was stunned to see how lifelike they are. Apparently these are real, and you can potentially buy them in the US also for around 60$. The jellyfish also changes color according to its "mood". The company that imports them is called RoboToys, although they seem to be out of stock for the moment.

One of the newest and most advanced robot fish was presented in a London aquarium. The robot fish seems to be able not only to keep it's equilibrium in the water, but also to detect it's surroundings (aka doesn't bump into the glass wall of the aquarium ). That's pretty neat, so congrats to the guys from Essex.