I'd like to have different apps handle .jpg files based on a naming convention I'll use for the .jpg files. Specifically most will go to Xee, but ones containing thumb should instead cause VLC to be called with the same path and file name, but with .mp4 (or .mkv, etc.) extension.
Is there an existing script / app that does this? I'm guessing the way to do it would be to create a shim app (sort of like choosy) that handles the main file type based on extension, and then hands off to the apps you configure based on a ruleset.