The first time I saw this was some friends of friends who were trying to make it into a startup. They quickly discovered that their users liked the idea of a busy light for the office, but didn’t like to update it on or off throughout the day. So after the first few days people just defaulted to leaving it marked as “busy”. Within a week or two their coworkers realized that the light was always on busy, so they started asking if they were really busy.
At that point, the entire busy light idea had been defeated.
This product looks more versatile. Being able to automatically tie it to meeting status or set pomodoro timers could make it more interesting.
However, I predict the same fate: Eventually people will realize the light is busy when the person isn’t really busy, and then return to the old habit of interrupting to ask if they’re busy.