Heh, never really thought there's a market for it. Though now I can imagine it being sold at some TV shopping channel. A solution to a problem you never knew you had.
Anyway, I think there are plenty of people who do not want to open windows and still have fresh air. But the amount of people who can't modify their room or for whatever reasons don't want to open their bedroom door is bound to be much less.
Now I'm curious, why don't you open your bedroom door? Me, I'm a light sleeper and other apartment dwellers will wake me up if I open the door.
Anyway, I think there are plenty of people who do not want to open windows and still have fresh air. But the amount of people who can't modify their room or for whatever reasons don't want to open their bedroom door is bound to be much less.
Now I'm curious, why don't you open your bedroom door? Me, I'm a light sleeper and other apartment dwellers will wake me up if I open the door.