pngquant is a batch conversion utility to quantize and dither truecolor PNG images, especially those with a full alpha channel, down to "RGBA-palette" PNGs (i.e., PLTE + tRNS in PNG parlance). Such images are usually two to four times smaller than the full 32-bit versions, and partial transparency is preserved quite nicely. This makes pngquant especially useful both for Web sites and for PlayStation 2 development, where one of the texture formats is RGBA-palette-based (though not PNG-compressed).
The Enhanced MetaFile format (EMF) is the native vector graphics file format on Windows. Qt is a cross-platform application development framework, widely used for the development of GUI programs. Although it provides tools for almost every aspect of software development, Qt doesn't include a straightforward solution for the export of 2D graphics to the EMF format. EmfEngine covers this lack and enables Qt-based applications to easily export graphics to the Enhanced Metafile format.
A lot of stereoscopic cameras use the .MPO format to store two JPEG images, including the Fuji W1, W3, and a few 3D camcorders that have a still mode. It can do two things for you: it can separate out the image files into a left and right pair, so you can process them or do whatever you want with them, or it can create an anaglyphic image (the ones you need coloured glasses to view). It is simple to use from the command line and takes wildcards, so you could process a whole batch of files with: mungempo *.MPO.