Things that have been previously made that could be considered History Hacks (although not necessarily made at hackdays)

• Southampton Blitz Map - mapping where every bomb fell on the worst nights of the Southampton Blitz. 
• The Revolutionaries - Explore the history of science and find who influenced who. Made at Science Hackday.
• BBC Dimensions - The size of historical events and things overlaid onto a map 
• Open Plaques - Mapping and annotating all the commemorative blue plaques. Made at Yahoo Hackday 
• Paper Internet - Making a network of time capsule backups of the internet 
• Spacelog -  "Read the stories of early space exploration from the original NASA transcripts. Now open to the public in a searchable, linkable format."
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