I've been logging temperature from a ZigBee temperature sensor (located in my shed in the back garden) since about November last year. I thought it would be interesting to see the diurnal (daily) temperature variation over time. On the x-axis are days (from about 10 November 2011 to 7 March 2012) and on the y axis is time-of-day, with midnight being at the very top and bottom. Temperatures vary from about -3C (deep blue) to +15C (red). Periods where there is no data are gray. Sorry no legend or axis markings.
The chart was constructed by averaging temperatures into 15 minute bins (with about 5 samples per bin) and plotting each bin as a rectangle in SVG. I then used rsvg to convert to a PNG image.
For comparison here is a chart for the same time period of my home office temperature. The color scale is different, deep blue being 12C and red 22C.