Aside from this place I tend to frequent a few other forums.
First being Facepunch Studios. However, I would recommend that most people here avoid that place like the plague, as they're highly anti-anime (more like anti-Japan in general). Actually they're pretty much anti-everything except video games, and even in that regard they're somewhat anti-console as well as anti-several other things that are too numerous to count. Only go there if you like PC games and Garry's Mod, for discussions involving much else steer clear.
www.facepunch.comI also recently started posting on Maidens of the Kaleidoscope, which is a Touhou forum. Oddly enough it's starting to feel like Paradigm-City in its non-hostile nature (and choice of color):
http://www.shrinemaiden.org/forumAnother place I frequent is Hard-Light Productions, which is where most of the Freespace Open community is. If you like space-sim games or have an interest in programming, I recommend stopping by:
http://www.hard-light.net/forums/I have the same username on all of them.