Archive and Digital Storytelling:
Omeka
Mapping Geography/Spatial/Social Networks:
StorymapJS
MapBox
GoogleMaps
HyperCities
Stanford Spatial History
Timeline:
TimelineJS
TimeMapper
Timeline Setter
Data Visualization:
Google NGrams
Google Fusion Tables
Voyant Tools
Wordle
TokenX
visualisingdata.com
Tableau Public
Palladio
Feel free to edit and add to the list if you find more interesting tools.