Revoice Pro - Revoice Pro is an audio plugin used for vocal tuning, time correction and ADR.
Kontakt - With KONTAKT 6, you can sound like a snare drum, a symphony orchestra, or anything in between, from a universe of sampled instruments.
GSnap - With GSnap you can get an auto-tune effect.
UVI Falcon - Sampler/synth hybrid instrument
n-Track Studio - Audio recording and music creation app for iOS.
Pianoteq - Pianoteq is a virtual piano that runs on your computer.