Classy icons crafted according to Microsoft guidelines. Available in PNG and SVG. Free for a link
ImBatch - ImBatch is a batch image processor with a nice graphical user interface.
Feather Icons - Simply beautiful open source icons
DVDVideoSoft Image Convert and Resize - Free Image Convert and Resize is a compact yet powerful program for batch mode image processing.
IconStore - Free icon packs by first-class designers
Batch Image Resizer - Resize, crop, shrink, flip, exif-rotate, convert, enhance, process multiple pictures and photos with professional software! 120+ Actions, 30+ Image Formats
Flat Icons - 20,000 unique, customizable icons with free lifetime updates