Celemony Melodyne - Celemony Melodyne is the perfect quick and easy tool for all your tuning needs.
CrispyTuner - Fully featured vocal tuning suite.
GSnap - With GSnap you can get an auto-tune effect.
Revoice Pro - Revoice Pro is an audio plugin used for vocal tuning, time correction and ADR.
Voloco - Auto-tune made simple and funny for everyone
TalentedHack - A Pitch Correction LV2 plugin derived from Autotalent