The thing that struck me the most was the black ceiling- it completely erases the boundaries of where the room ends, and gives the illusion of much more space than is actually there.
"The bathroom is only about 5×6 feet, but the ceiling is more than 10 feet high! By carrying the white paneling and wall tiles to a uniform 8 foot height and then painting the upper portion of the walls and ceiling black, I was able to give the room a greater feeling of width and space. It’s an illusion that really works. I can’t believe how much more spacious the room feels now!"(source)
images sourceSo, when you're looking for a solution to make a space look and feel bigger, don't rule out black. It really can work wonders.