MusicDevelopments has released MIDI Mutator

[cclarry]

a plugin that can modify any aspect of a MIDI sequence: rhythm, timing, accents, chords, voicings and shape.

The price is $49, but during the Summer Sale, until June 26th, it can be purchased for $29 (40% off).

http://www.musicdevelopments.com/midimutator.html

[Brian Lawler]

This is from the developer of Rapid Composer and MIDI Mutator is a new tab in RC 4.4 (also just released)