lmp3 walks a directory structure in search of MP3s. It has some nice features, like hunting down lost MP3s or quickly generating a list of MP3s and feeding it to mpg123.
Open source project that offer summary and download services on this page is a project that carry out their development work on other open source development sites. Their work is linked to this page via a feature called OFI, and their work is not carried out here on OSDN site.