Here in central EU, at about 17:35 the forum _is_ slow... Like: I'm reading a topic, I hit "replies" and it works fast, then I hit the back button and... 5 to 10 seconds! Not always, but often enough to make me look for topics like this :-)
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PS: are there any public stats about this site ? Anything one can take a look at and try to help ?
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Found this old post: http://arduino.cc/blog/2008/05/02/web-statistics-at-arduinocc/