Not Rom Records (website no longer available) has released NRR Filter v1.00, a freeware simple filter VST effect plug-in for Windows.
The filter has the usual Cutoff/Resonance controls and features LFO modulation.
Note: Beware of using high values for the resonance (knob marked ‘r’ on the interface) as you may end up with some ear-piercing screams.
You’ll need to register for a free account to download this filter plugin.
Visit Not Rom Records (website no longer available) for more information.