I worked on this tool for my old group as a means to organize their arrangements. Alas, alas, alas, as side projects often go, it was never completed. Nonetheless, it was a fun journey.
The process involved migrating from physical drawers containing hundreds of pdfs loosely alphabetized into a searchable, easy to use, online tool with super fun and super rad metadata.
The database itself is written in CouchDB (a NoSQL db) and takes advantage of its notions of views and its quick map reduce. The files themselves are stored on backblaze for its combination of speed and cheapness.