An exciting discovery: the air in my home gets extremely dry in the winter and it irritates my nostrils, but I just had the idea to take one of my cloth masks from the early days of the pandemic, run it under some water, and then put it on. Now any air I breathe in is passing through a layer of damp cloth first, so it's like an extremely localized humidifier. (I have an actual humidifier too, but this solution has a much more immediate effect)