A few months ago, we loaded up the publicly available Ubuntu archives and subscribed to their active lists. MarkMail now searches 313 Ubuntu lists and 1,917,153 messages. The first Ubuntu list started in July 2004 and there are currently 200 active lists, recently accumulating 4,061 messages per day.
Ubuntu is very much a world-wide project. Below is a recent snapshot of the message counts for Ubuntu lists associated with specific counties: