Recently checked out and bought a plugin called SoundBrigade by SKnote.
The developer describes it as a "Brigade of filters".
Basically, one of its uses (or "missions" as the dev puts it) is that you assign it to a certain frequency range (ranges from one octave to the full spectrum) and pull the threshold down, and it tries to even out pokey frequency peaks.
A quick test with a mastering job seemed to work well; I had a techno tune which I was almost done with, but the kick was hitting maybe 2 dB too loud compared to my trusted reference tunes. I set the range to roughly cover the kick area and pulled the threshold down – and hey, what do you know, it did exactly what I was hoping it'd do.
Still to explore the other "missions", but I know that I'll be using the master one. Probably best for subtle use.
The price is very nice, too (yes, I bought it).
Check it out:
What was the last plugin purchase that you were happy about?