Digidesign has released Pro Tools TDM 6.9.2 update, which brings Tiger support to the Pro Tools 6.9 feature set.
Unfortunately, this update is "for Pro Tools|HD systems only. Future Pro Tools software releases will support Pro Tools LE systems and Pro Tools M-Powered systems on Mac OS X 10.4."
In case, you don't know what Pro Tools is, it's professional grade audio-production software. In SAT-speak (for all you graduating high-schoolers): Pro Tools is to Logic what Avid is to Final Cut Pro. Although, I tend to think Pro Tools is better than Logic, whereas FCP is better than Avid. Disagree? Discuss in the comments.