Datrio
Dariusz Siedlecki - born 3rd November, 1988, he's an active Wikipedian from the early 2005. He's been a lurker for almost a year, when he observed the development of the polish Wikipedia. Mainly, he translates the Wikimedia Foundation or Meta pages into Polish. Also, thanks to his knowledge of PHP and MySQL, he's a Mediawiki hacker in his free time.