Interactive Autonomous Dynamic Systems (IADYS) has developed a type of Roomba to clean rivers.

It is called the Jellyfishbot, and it tools around a river picking up plastic and other trash very nicely.

Yes, I know, it does not look like a jellyfish. But if you are an eco-terrorist then you need some of these.

Autonomous and handy, the Jellyfishbot is a multi-purpose solution for the collection of waste and hydrocarbons on the surface of water bodies