The background picture has changed twice in a couple of days. Actually the last change is only a contrast change. So now the background picture is a picture showing some clouds seen from above them. Well, it's also showing a part of Earth. I simply shot the picture when I was in a plane, flying from Nice to Paris. Of course there are modifications because the genuine picture is not like that... And to cheat a little bit, the picture is present twice : below it's upside-down... Here is was the link to the picture.