Ask HN: Examples of businesses built on open data?
I'm looking at examples of businesses built on open data - such as
1. Selling the data itself - like, take data from the govt, clean it, massage it etc and sell it
2. Services built on top of open data
3. Scraping - data that is not readily available in machine readable format, but can scraped (web pages, PDFs etc), packaged and sold.
Anyone knows examples of such?