Engineers at Virginia Tech have developed an autonomous jellyfish weighing 170 pounds and measuring nearly six feet in length. It's called Cryo, and it's part of a U.S. Navy funded project that could turn these life-like aquatic robots into spies.

Cryo is equipped with eight mechanical legs that circle around its metal chasis. Its body is made from a big blob of soft silicone (the same kind of material that's used to make masks in movies). Cryo gets around by mimicking the way real jellyfish propel themselves through the water, which is by pulsating its umbrella-like frame to produce locomotion.

Given its low energy demands, it's hoped that the robotic jellyfish can work independently for weeks or months — if not longer.

And as noted, it could eventually be used by the U.S. military for surveillance purposes. Aside from that, it could be made to monitor the environment and clean up oil spills.