Last week I stumbled upon the long exposure image of firefly tracks. I like the image and I also would like the idea to analyze if there are common patterns in their flight...

Here is a similar picture for all the people who own a Roomba vacuum cleaner from iRobot - or who consider to buy one. This cleaner tries to reach the complete room automatically:

As you can see: the Roomba cleaner hits every place in the room - at least better than I probably do. Here we also have more data than in the firefly setting and this allows for a first (human) analysis: it might hit every single spot - but it seems to work quite inefficient. However, I like the circular shape in the left part and I wonder if the left part of the room had actually more dirt since the Roomba stayed longer  there.