http://reverland.org/python/2013/01/28/visualize-your-shell-history/
https://github.com/reverland/scripts/blob/master/python/tagcloud.py
https://github.com/atizo/PyTagCloud/blob/master/pytagcloud/test/tests.py
https://github.com/atizo/PyTagCloud/blob/master/pytagcloud/__init__.py
http://www.maketecheasier.com/5-online-tools-to-create-tag-clouds/2012/01/10
http://tagcrowd.com/
http://wordcram.org/2013/03/03/wordcram-0-5-7-released/
http://whydoidoit.com/wordcloud-for-silverlight/
http://stackoverflow.com/questions/342687/algorithm-to-implement-a-word-cloud-like-wordle