John Heideman’s team at the University of California has drawn a map; in fact the study is called “when the internet sleeps”, but as the world is divided in time zones, the map is a good way to render the results. It is an animation showing the answers of an extraordinarily large amount of IP addresses to a ping testing whether they are on or not every 11 minutes for 35 days in 2013. The map shows that during the nights the computers in Europe, Japan, South Korea and  the USA (along with phones and other net-connected devices) are often always on, or at least much more often than in other countries with lower revenue. The reasons are being studied, and the text and graphs of the original website provide more information.