Dia

Dia files are created with the package of the same name and consist of diagrams (flowcharts, network diagrams, UML, etc). The program is an open-source alternative to such things as Visio. Dia files are binary in nature. It is not connected with the museum in Beacon, New York or the Spanish supermarket chain.

Dia software is able to export to other formats:
 * PNG
 * SVG
 * etc

Software

 * Dia Diagram Editor

Links

 * Official site
 * Wikipedia article