Discussed only 1 month ago: http://news.ycombinator.com/item?id=4616548 http://news.ycombinator.com/item?id=4616548 There is also a 3 year old discussion: http

Discussed only 1 month ago: http://news.ycombinator.com/item?id=4616548 http://news.ycombinator.com/item?id=4616548 There is also a 3 year old discussion: http://news.ycombinator.com/item?id=633151 http://news.ycombinator.com/item?id=633151