On a youtube video my wife and I saw this toy with thousands of ball bearings sandwiched between two panes of plastic. We both thought it was cool and she particularly wanted one. Well, I looked around and found it was a desk toy from 1966 called Atomix and didn't exist anymore. So, the answer is obviously to make one.
Step #? in baby proofing the house, the great baby wall. The living room is our safe zone and the kitchen by nature is not. There is a big 11ft opening that connects the two and since we wanted to separate them we needed something that the kids couldn't knock over that spanned that big distance. I didn't think anything on the market would works so I made a fence to keep them out.