Mindup: free, opensource, online mindmapping canvas
MindMapping.com Information and history of mind mapping
Mind-mapping.org List of all mind mapping, concept mapping, outlining, diagramming and related types of tools.
ThinkFree - Graphs, spreadsheets and presentations
Create A Graph
e-Tutor Graphic Calculator - Graph equations
FooPlot - Online plotting tool
PDF Pad - Create and print graph paper
Dipity's mission is to take the most useful information on the Internet and organize it by time. By providing digital timeline technology, Dipity allows users to gather real-time sources from social media, traditional search services and RSS to aggregate them in a single, easy to use, fun to navigate interface.