Pencil Project – Free diagraming and prototyping, Also run as Firefox addon

The Pencil Project’s unique mission is to build a free and opensource tool for making diagrams and GUI prototyping that everyone can use.

Top features:

• Built-in stencils for diagraming and prototyping
• Multi-page document with background page
• Inter-page linkings!
• On-screen text editing with rich-text supports
• Exporting to HTML, PNG, Openoffice.org document, Word document and PDF.
• Undo/redo supports
• Installing user-defined stencils and templates
• Standard drawing operations: aligning, z-ordering, scaling, rotating…
• Cross-platforms
• Adding external objects
• Personal Collection
• Clipart Browser

WebSite: http://www.evolus.vn/Pencil/Home.html