Do we ever really think about nothing? It's a hard question to answer, but if you're wondering what it looks like, this is the result of an experiment by artist Gustav Metzger, who hooked himself up to a robotic carving machine while he took a long time thinking about absolutely nothing. We wonder how he did it.

The machine measures electrical signals from the brain, and uses them to dictate patterns it cuts into a piece of Portland Stone. The result is of course, art, but we can only imagine this kind of art to look different for everyone else if they were to hook themselves up to that machine too.

The sculpture is on display at the Work Gallery in London until February. [Design Week]