QuoteOh, I was thinking of more of the kind of reverb you hear in dark ambient and a lot of PE. It makes it sound kinda spooky
So, just some standard utter cheesy reverb. A rackmount or desktop reverb unit of some kind might be better than pedal ones, because reverb pedals are for guitarists and thus are mostly boring and limited. Some Alessis reverbs can be picked up cheap on eBay etc, also the Zoom rackmount multi fx like RFX1000 or similar are cheap and have some decent reverb settings
For actual interesting/good/experimental reverb try things like as mentioned playing back and recording sounds in a real reverberating space (yeah a giant hall might be more like echo but that could be good, and in a way reverb is kind of just really short echo anyway, but even a tiled bathroom can make a good reverb chamber!) ...or since reverb is usually (except spring reverb) a digital effect just forget pedals and experiment with Convolution reverb in software. Can't be bothered to explain it now but long story short it's magic, you can kind of sample a real space and put any sound thru it for super realistic reverb as if it was being played in that space. One of Reaper's default verb plugins can load 'impulse response' samples, and you can download a lot of them free online, I've found forests, caves, Masonic temples, warehouses... Also you can load in samples that aren't intended to be a reverb impulse and make your own unnatural spaces/atmospheres. I made a dark ambient/drone track by playing sounds thru a riff from a death metal song, it sounded like some giant doom cathedral
Anyway I'm not explaining this so well, Google 'convolution reverb' and read up about it and if you don't get excited about it you prob shouldn't be doing reverb-centric electronic music :D