BlueLab released Infra, a powerful bass enhancer plugin. It uses the phantom fundamental psychoacoustic phenomenon, and also adds a sub octave frequency, to increase the bass perception of any bass sound.
Phantom fundamental, or missing fundamental, is a psychoacoustic phenomenon that makes hear a frequency that is not present in a sound, by using a particular arrangement of harmonics.
The Infra plugin adds such harmonics to a sound and makes hear a bass sound stronger than it is in reality.

Price: USD 30.00$

More info here:
BlueLab | Infra