If you've got five minutes, I think these threads covered this fairly extensively--
viewtopic.php?f=149&t=62751
viewtopic.php?f=149&t=58058
(dirty and or self-oscillating)
Paradox Arquitecto
Keeley Gold Star
Industrialectric RM-1N
AC Noises AMA
SolidGoldFX Counter Current
Catalinbread Adineko
et cetera...
higher-end reverbs recommended by the board:
Mercury7
Space
Atmosphere
I still lean on an Empress in the lo-fi settings. The Dark World doesn't have dedicated drive, but it can do fairly gritty textures. It's better at delivering more feral sounds than nearly anything else I've personally used.
Here are some recent releases:
Pinebox Sirens (lo-fi modulator for pairing with delay/reverb)
KMA Cirrus (delay/reverb combo box for ambient stuff, not necessarily lo-fi or nasty)
Also, the MOOD can do a lot of atmospheric stuff in reverb-esque territory, even when you're using one of the 5 modes that isn't Reverb.