AudioThing releases free equalizer plugin Blindfold EQ
Blindfold EQ is a freeware EQ plugin inspired by a quote by Matt Wallace from the book Recording Unhinged by Sylvia Massy.
It has 4 bands (LowShelf, LowMid, HighMid, HighShelf), but each knob is blind. There are no indicators or numbers to show frequency values, gain values or Q values.
You have to use your ears.