For future readers: Mentioned diagramming programs/apps http://www.diagram.ly http://www.diagram.ly (based on mxGraph, a javascript lib) http://www.lucidchart

For future readers: Mentioned diagramming programs/apps http://www.diagram.ly http://www.diagram.ly (based on mxGraph, a javascript lib) http://www.lucidchart.com/ http://www.lucidchart.com/ http://www.gliffy.com/ http://www.gliffy.com/ (requires flash) https://www.circuitlab.com/ https://www.circuitlab.com/ http://www.umlet.com/ http://www.umlet.com/ (download) http://www.flowchart.com http://www.flowchart.com http://docs.google.com http://docs.google.com (drawings not diagrams) gojs.net (still in private alpha) I'd add that I've tried: http://www.lovelycharts.com http://www.lovelycharts.com http://www.cacoo.com http://www.cacoo.com (flash)