Background: I've got a folder full of saved desktop pictures. I'd like to put them into folders, based on their resolution - 1024x768, etc. Creating the folders on the fly is a bonus. Currently, the images are all in a folder, but some of them are in sub-folders. I can merge them by hand, if that makes things easier.
I'd prefer the terminal, though I'm still kind of a bash newbie. I'm not much of a programmer at all, really.
I'm using Mac OS X, but I'm not opposed to installing extra apps to accomplish this (MacPorts?), or even using another OS (I've got Windows XP, Windows Vista, and Ubuntu 9 setup right now within VMWare).