Regardless, I'm struggling to know the audience here. Is it an employee in the office? If that’s the case, it won’t solve any problem because most of the disturbances happen from your boss either calling about something or asking you to join another useless meeting. Your boss won’t care about your status simply because they won’t be collocated in the same office as you most of the time (not that they care about your online status anyway). For colleagues, after the first month or so, everyone will pretty much find the best way to approach others. If you still need a device for that, then there’s a problem in communication that you need a persistent device all the time. At home, you won’t need such a thing. So I don’t know who will find it useful; it looks gimmicky. What’s next, a hat that will turn a green light telling people you are approachable or in the chatting mode, and red when you are not?!