Mildon Studios has released Vocal Spread, a new VST effect plug-in for Windows that spreads out the signal across the stereo track, which can help the vocals steer clear of the muddy areas (like bass and kick in the middle) while keeping it bright and centered.
The 'body' fader can help make the vocals sound more up-front, while the 'spread' fader controls how much of the signal is spread across the 2 channels. It also applies a very short delay to some parts of the signal for maximum effect, but this feature can be turned off for mono use.
This plug-in was designed to be used with vocals, but it can also be used for other instruments and sounds.
Vocal Spread is Donationware, with a minimum donation of $3.