My main contributions are the vectorization of images. If they take less then 3 hours to be done, I think they are simple enough to be put in the Public Domain (if the original/derivative works in also in the Public Domain). If they take more then 3 hours to be done, I put them under CC-BY-SA or GFDL.
Here the vectorization I've done :
- see the gallery
If you find errors in the images, I'm happy to correct them.