Digg uses Debian GNU/Linux across the board with a mixture of MySQL, Memcached, MogileFS, Python, PHP, Apache, Gearman and various appliances to serve up billions of requests a month (and more every day!) (via How Digg works)
About
Alberto Escarlate is:
CTO, co-founder at TigerTag
Chief technology consultant at YellowPin
Advisor at Next Generation (startup incubator)
Faculty at Parsons New School of Design
Twitter: @cacheop
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