Nerd out with Lingvopedia
Adam, whom I met at the Polyglot Gathering in Bratislava earlier this summer introduced me to Lingvopedia. It's an encyclopaedia about European languages in all different European languages — 784 articles on languages! Go find out fun facts about Maltese, Bulgarian and more!
Thanks, @Ave, it's awesome!
I've just checked it and must warn the rest you may end up like this if you like languages like this racoon likes sweet pastries: