I recently ported over an older project to a new site, and from a PHP back-end to Python.
The new version is Python Django/NLTK based.
The previous version had used a custom PHP backend – with some third party code.
The initial tables are nGrams from n=2 to n=6, and the refined tables are nGrams on text that has been NLTK filtered to include only certain parts of speech.
wordintel.com is part of a larger project that I plan to develop into a fuller data extraction/summarization/search platform.
The home page is just a visual concept demo for now, but in the future at some point I should be able to hook up a functional back-end.