Building a media collection is much more fun than organising it, and no matter how good your intentions, it’s all too easy to end up having to navigate a scattered mess of audio and video files.
MediaPurge is a freeware Windows application which provides several ways to restore order, including finding audio duplicates, tagging, renaming or sorting files into a new folder structure.
The most interesting tool is probably the duplicate file finder. As well as locating duplicates by file information (size, tags) or content, it can also use acoustic fingerprinting to match similar files, for example two different rips of the same song.
The latter option worked well for us, and runs reasonably quickly considering the work involved, processing around 10 songs a second on our test PC.
MediaPurge can also bring order to a cluttered "Music" folder, building new folders based on file names or tags and sorting your files accordingly.
There are automated tag management tools to edit, copy or remove ID3 tags, rename a file based on its tags, or generate and assign tags from its file name.
MediaPurge also includes a sync tool for comparing two media collections, finding and ignoring duplicates and synchronising everything else.
There are some interface oddities, particularly with the English language translation (the original German is visible in several places). MediaPurge is still very usable, though, and its acoustic fingerprinting abilities are enough to justify the download all on their own.