ImBatch - ImBatch is a batch image processor with a nice graphical user interface.
Artsy - A global platform for discovering and collecting art.
Ralpha Image Resizer - High-speed image batch conversion tool
ArtMajeur - +1 Million original artworks, Free Shipping Worldwide, Low prices guaranteed, 14 days return: buy all the art you love on Artmajeur!
Batch Image Resizer - Resize, crop, shrink, flip, exif-rotate, convert, enhance, process multiple pictures and photos with professional software! 120+ Actions, 30+ Image Formats
Magnus - Shazam for art