Wad Builder
From DoomWiki.org
Wad Builder is a very basic WAD file editor for MacOS X, created in 2004 by Sarah Mancuso (esselfortium). It has two basic functions: exporting a WAD's lumps into a folder, and recompiling that folder back into a WAD. It only has very basic features, but can be used to install FraggleScript scripts, DeHackEd lumps, MP3 or OGG music, edit plain-text lumps, and move or rearrange any lumps back and forth between WAD files.