If I need real digital grit I go with the reverb on my Ensoniq ASR-X or some other hardware digital reverb from pre-2000, preferably pre-95. I got my ASR-X for the price of your standard prosumer plugin ($150). There is some downsampled magic going on in the algorithms on those FX chips that simply can't be had in the box. You might consider investing in a used hardware unit.
If I must stay in the box, you can get pretty gritty results by using a vanilla reverb plug in on a send channel (I use Ableton's native plugs), use a saturator as an insert (or as a parallel chain if on Ableton like me), EQ as a needed, then introduce the saturated reverb to taste, even use 100% saturated reverb if you want that early 80's low-budget disco funk sound, which is what I was originally going after with this technique. Really, just throw anything after the reverb and see what happens. Formant EQing generates interesting ringing tonal artifacts on reverb, bitcrushing is rugged, vocoded reverb is wild, I've even resampled the reverb and applied some FM modulation with Ableton's Sampler. For totally crazy spring reverb FX, use a delay, preferably a ping pong, then set the period to various millisecond intervals and a really high feedback. With Ableton's ping pong, I typically modulate the interval with a knob, creating crazy Doppler like effects, and if the delay fade setting is set to repitch, I get crazy repitching as the delay adjusts to the new delay period. Used as a parallel insert over a vocal or something, sounds pretty wild, like the vocalist is getting sucked into a black hole. Works well on electronic styles like deep house, future funk, etc... where no one knows the rules so there are none to break. I think you can do a hell of a lot if you just start smashing your plugins together