Among the most often requested, but still unsupported by Inkscape, file formats are Flash (SWF) and Adobe Freehand. For data exchange with Adobe Flash or Adobe Freehand, you can use SVG or PDF formats, but direct support of these important formats would be preferable. Fortunately, it is very easy to plug in a new format into Inkscape; as soon as there’s an open source utility which can bridge from one of the known formats (ideally SVG, but PDF would work too) into the unknown, incorporating it into Inkscape is easy.