Avanti GUI is a free portable audio video conversion tool with a graphical front end. It allows a user to convert for example: "FFmpeg codecs" such as Mpeg, AVI, Xvid formats.
mp3DirectCut is a portable mp3 audio editor and recorder. It allows a user to directly cut, copy, paste or change the volume with no need to decompress your files for audio editing.
Wavosaur is a portable and Free Audio wav and mp3 editing tool that allows users to easily edit/remaster audio in multiple formats. It can be used to edit, process and record various sounds including wav and mp3 files.