Okay, if you purchase and keep around a machine that sprays you with hot soapy water... you are a design snob. Or, more likely, you're just using something as an extended metaphor. Can you REALLY not know when it's on? Or is it just for the purposes of this article. They love to take literary liberties at 37Signals. I can imagine it happening a few times, but it's likely there is some indication that it's on and a slight bit of attention paid to that keeps you from making the same mistake.