BrawlLib / BrawlBox
BrawlLib and BrawlBox are designed to edit various types of data files found in Super Smash Bros. Brawl. They were developed initially by Kryal (http://code.google.com/p/brawltools/source/list), then by BlackJax96 (http://code.google.com/p/brawltools2) until the end of 2013.
Current BrawlBox contributors are libertyernie, Sammi Husky, and BlackJax96.
The official forum thread on KC:MM is here: http://forums.kc-mm.com/index.php?topic=67847.0