Arctican has released The Pilgrim, a free VST filter effect for both live and studio situations.
It has a highpass & lowpass filter programmed into one dial, and allows a seamless sweep between the two. It works similar to the ‘Pioneer DJM’ mixers, albeit with a little extra functionality: a wet/dry dial which can also be used as a basic equaliser/shelf filter. The frequency pass range is from 60Hz (lowpass) to 19kHz (highpass).
Pilgrim is available for Windows (VST) and OSX (AU and VST).