Valhalla DSP ValhallaFreqEcho
Simple yet flexible
This is, considering it's simplicity, a pretty complex plugin. It can act as a barberpole phaser, flanger, and, of course, a delay. It's fun to program and automate, and has the ability to transform a drum track into what sounds like a complicated percussive soundscape like something Autechre would use, or replicate the frequency shifts of a track by t e l e p a t h ????????. Definitely would (and have done so) recommend to anyone who produces in a DAW.