Serato's Pitch 'n Time has carved out a reputation as one of the best time-stretching and pitch-shifting plug-ins out there, with special features including 'morphing' time-stretch and the ability to recreate varispeed effects.
If you need a new way of adapting the feel of a loop, or you want decent pitch-shifting and time-stretching on a budget, Psoft's inexpensive utility might be for you.
A Powercore version of Antares' ubiquitous Auto-Tune pitch corrector was announced in 2001, but it never appeared. Is TC's new Intonator HS plug-in a viable alternative?