I did something similar around 2009. You used to be able to sell RSS feeds on the Kindle, so I created a number of twitter bots that simply aggregated news from a variety of sources on a variety of topics and used Yahoo! Pipes to turn them into RSS feeds. Made about $10 - $12 a month for several years from that until they discontinued the service.
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[ 2.4 ms ] story [ 12.6 ms ] threadhttps://news.ycombinator.com/item?id=20419756
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