Linux Show Player - Sound player designed for stage productions
GSnap - With GSnap you can get an auto-tune effect.
QLab - QLab, Live show control for Mac OS X.
Revoice Pro - Revoice Pro is an audio plugin used for vocal tuning, time correction and ADR.
Trigger Audio and Video Playback - Audio and video cue player for broadcast and live performance.
Celemony Melodyne - Celemony Melodyne is the perfect quick and easy tool for all your tuning needs.