Retouching examples
There are loads of "fun" images at WPClipart, but a big part of what is being attempted here has to do with historical/research value. Maps, geography, flags, historical figures, American History, rocks and minerals, religion, mythology -- these are not popular or fashionable image groups, but they can be quite useful in documentation, school papers and, ultimately, to enable people to get a more visceral feel for who and what the images represent.

Toward this end I have done a lot of retouching of images, at times taking some "artistic license" by manipulating the originals. I can attest that in the case of historical photos, this is never done with an eye to change any impression put forward by the original -- editing is done first and foremost to ensure that if a visitor needs to reprint the image, usually scaled down and on a modest inkjet printer, then the details of the image will still be visible.

Below are a few examples:

Original

Retouched

Rendered SVGs