Create a list of your mp3's. Include info of your choice (size, time, bitrate, stereo mode, path, date, etc). Save in internal format or export as text, html, xls or m3u.
Import lists created by other applications. Find duplicates in your list. Compare your list to other people's lists (find out what others have that you don't, and the opposite).
Insert & edit items. Plenty options to satisfy almost anyone. NOTE: by registering mp3 List Maker De Luhe, you get other two handy mp3 utilities for free: mp3 Frame Editor (editor with no encoding and decoding back to mp3 - loss of quality) and mp3 Frame Remover (simplified version of mp3 Frame Editor, used for easy trimming of mp3 files).