This side is no longer needed, because there is a fd.o Mailinglist now: http://freedesktop.org/mailman/listinfo/clipart
We can use this as a Mailinglist Replacement as long as we don't have a real one.
I would vote for a 100% SVG clipart project. Every thing else, like PNGs or WMFs can be generated by scripts.
You can convert Blender files to SVG fils via a script you can find here: http://home.referral.net.au/thesethings/svg/