We built the Adafruit Internet of Things Printer last week and, after playing around with it a bit, we settled on tracking a twitter feed of local weather (this has lent itself to all sorts of jokey comments about it not really being whatever outside until the twitter feed through the printer confirms it).
However, it also turns out to be a surprisingly clever UI. We correlated people getting headaches with the barometric pressure changing over the weekend. Could we see this by looking at the twitter feed on a computer? Sure - but we've never tracked the weather that way before. There's something very natural feeling about a length of paper with points in time along it (blame it on growing up with timelines in classrooms).