HaasPan will pan mono signals with psycho-acoustics. The effect simulates the way we perceive direction in real life and at times sound more natural than a standard pan knob.
pHaasE will delay the side information and thereby create a whole new stereo-image. This is, according to Noisebud, a highly experimental plugin and should be treated with care. They say that the result can be both stunning as it can be dreadful.
Both plugins are free but you are encouraged to donate to support continued development.