With version 8.0.3, Digidesign has brought Snow Leopard compatibility to its professional audio editing software Pro Tools [1], which also now requires an Intel-based Mac. In general, Pro Tools 8 offers a refreshed interface, the capability to work with three times as many audio tracks, an added Score Editor, a new MIDI editor, an Elastic Pitch feature, and new track compositing capabilities. (New purchase and upgrade prices vary widely.)
[1]: http://www.digidesign.com/index.cfm?navid=354&langid=100&itemid=35911