Now that we've open source'd Duke, it's possible to use the Duke Mascot (technically Duke isn't a Logo but a Mascot, as I understand it) for any aspect of the Java ecosystem. Way back in the mysts of tyme, in the 1.2.2 and 1.3 timeframe, I helped to put the java.awt.Robot class into the platform. In 1.2.2 we had a private class, and in 1.3 we upgraded it to a real honest-to-goodness class for the platform.
Around that time I had this inspiration to draw .. Robo Duke.
As I sat with the regular Duke image it struck me. The essence of Duke is curved lines everywhere, but that's not very robotic. Robotics and machines imply (to me) straight lines, nuts, bolts, gears, etc. I'm sure Robotics experts might disagree, and for that matter my Roomba floor sweeper is an example of curvy lines on a Robot. Be that as it may, straight lines was my inspiration for RoboDuke.
This image has been in hiding all these years because, well, I didn't think the company lawyers would appreciate it. Lawyers tend to have low humor levels. But today it's different.
The following image is a PNG file produced using Fireworks. I just checked and if you load it into Fireworks MX (the latest version I have on my Mac) all the shape attributes are editable. Perhaps someone with some more artistic talent or, e.g. Inkscape expertise, can convert this to SVG or some other more openly editable format.
FWIW, I looked at duke.dev.java.net and don't see a way to contribute artwork. That is, other than to request a "Developer" role (which I just have).