Gliffy: Web Diagramming Tool
I mentioned the Dia (Open Source) diagramming tool for Linux and Windows a few days ago. But, if you use a Mac or don't want to install anything, take a look at...
It is a free web diagram creation service that also allows you to share the diagrams you create. It can also save the diagrams in the SVG (Scalable Vector Graphics) file format. You can import this file into numerous client-side diagramming tools.



Gliffy is pretty cool. It
Gliffy is pretty cool. It would be neat if you could add comments to objects and have them pop-up when moving over or clicking on the object.
Or if you're a developer
Or if you're a developer mxGraph. Doesn't even need the flash plugin, entirely native on each browser + you can get the source.