Photo Frame is a much simpler version of the full-frame script that uses rectangular frames. I find it useful for publishing photography on the web as it automates a simple task that I need to do repetitively when processing my digital photos.
Full Frame simulates full-frame photographic printing, which I've always liked for my printed photos. It even tries to simulate the aberrations on the ersatz enlarger's negative holder. It's not very successful, but I'm working on it. At least it looks slightly more realistic than most of the alternatives.
Duotone simulates sepia toning and other toning processes. Subtly toned black and white photographs look much warmer and better than ordinary greyscale ones. Duotone works like darkroom toning processes, it modifies a photo's midtones.
