Two spring to mind, both of them superb.
Objeq Delay is, obviously, a delay, but you can turn off the feedback and use it purely as a resonator. Probably worth checking Knobcloud and the like, as it was given away as a freebie at one point, so there may be some cheap licenses available, though why anyone wouldn't want to keep a hold of it is beyond me!
Supermodal is incredible. The way you can smoothly modulate between models allows creative filtering that isn't like anything else in my collection. Top notch stuff, as is their latest, Filterverse.
Perhaps if we all ask nicely
@Peter V will release it as a standalone, and if we ask really nicely perhaps he'll add the Resonator to Love. Here's my go "
Pretty,
pretty please,
with sugared almonds ontop!"
Supermodal uses hundreds of resonating filters to emulate the behavior of various resonating bodies. It contains 27 different filter models ranging from acoustic to synth-style to mathematical to special effects.
polyversemusic.com
Objeq Delay is the best acoustic filter and delay plug-in in VST, Audio Units (AU), and AAX formats for Reason, Live, Logic Pro, Pro Tools, Cubase, Reaper, Sonar, FL Studio, and many more. Try Objeq Delay for free.
www.applied-acoustics.com