How I Made Money Spamming Twitter with Contextual Book Suggestions | Charles Hooper

http://www.nytimes.com/imagepages/2010/12/15/15RARE1.html via Charles Hooper:

Two winters ago I left a position as a system administrator that was paying pretty well and moved cross-country to a region with less jobs than where I moved from. Three months later, I was still unemployed, broke, and bored. I was talking to my good friend Japhy on IRC one day and he was explaining to me how the tf-idf algorithm works. For reasons involving boredom more than any other reason, I dreamed up an idea: I would write software that would take a given document and generate book suggestions based on its content.

My imagination dreamed up this fairly straightforward process:
  1. Take a given document and calculate tf-idf scores on all terms
  2. Select X number of the highest scoring terms
  3. Pass these high-scoring terms to an Amazon ItemSearch query
  4. Receive a list of recommended books (with URLs) from Amazon….
This has a happy honest ending, for those with ethical concerns.