Anonymously judging other people on the internet is easy, but doing it well can be difficult. Enter Pic Nix, a free service that lets you casually (and anonymously) shame a fellow Instagram user for over-posting one of "16 offenses" like too many photos of beer, cats, food, lattes, or dreaded selfies. Ad agency Allen & Gerritsen, which came up with the project, has put together a warning image for each of these that can be posted on a @PicNixer account on Instagram, and will call your friend by name and offense in the comments.

Shame in a 1:1 square ratio

What makes Pic Nix particularly noteworthy is what's going on behind the scenes. Your image and a corresponding message are chosen and pecked out on a smartphone by robot the group has called Silent B.O.B. It types with a stylus that's hooked up to an Arduino-powered X-Y plotter that guides it to the precise parts of Instagram's app. The messages in each post (complete with an @ mention for your target) are then typed out on a nearby Bluetooth keyboard, and it's sent on its way (more on the whole process can be seen here).

Silent B.O.B. may not be limited to Instagram shaming, Allen & Gerritsen says. The group says it could use it for "brand experience" on its clients, meaning limitless callouts for less — or more — duckface.