One of Tim's main message was that government should put all its data online. No matter what format, just upload it. It is public data anyways, owned by the taxpayers.
To illustrate the powers of raw data he mentioned a blogpost by a british government worker who published data about bicycle accidents in the UK.
The story led to a strain of comments complaining about the proprietary format. Once someone posted the data in an open format, people where wondering how the X&Y coordinates in the spreadsheet would look on a map. So someone created a kml-file. Now people with GIS software could see the data.
Finally, someone took the government spreadsheet data from a simple blogpost, and created a real interactive map with it.
Tim's story is actually documented online.
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