Linux Show Player - Sound player designed for stage productions
Show Cue System - Show Cue Systems
Cue Player - Cue Player software for theater sound and lighting
QLab - QLab, Live show control for Mac OS X.
Trigger Audio and Video Playback - Audio and video cue player for broadcast and live performance.
CasterSoundboard - A soundboard for hot-keying and playing back sounds. (For podcasting)