ImBatch - ImBatch is a batch image processor with a nice graphical user interface.
FILEminimizer Pictures - FILEminimizer Pictures compresses JPEG photos, TIFF, BMP and PNG images and pictures by up to 98%.
Batch Image Resizer - Resize, crop, shrink, flip, exif-rotate, convert, enhance, process multiple pictures and photos with professional software! 120+ Actions, 30+ Image Formats
Caesium Image Compressor - Compress your pictures up to 90% without visible quality loss.
Phatch - Phatch = Photo & Batch!
Shrink O'Matic - Shrink O'Matic is an AIR application to easily (batch) resize (shrink) images.