There are almost too many examples to cite (narwhals, 'let me tap that', 'FB girl who loves anal', 'stay hasty' personal army thread, references to pedobear, etc, etc, etc).
Don't get me wrong. I love reddit. I also, in spite of myself, like /b/. It can be brilliantly demonic. But I've seen reddit slowly transform into /b/ over the course of the past 2 years - right around the time Anonymous went after the Scientologists. Amazingly, I have never seen reddit mentioned on /b/, but I see /b/ mentioned on reddit quite a bit. So how did it happen? Did reddit discover /b/ or vice versa? Is /b/ the inevitable end result when a bunch of smart, socially awkward, computer savvy teens and 20-year-olds get together online?
A long time i was sceptical that the system with the sub-reddits is really useful, but now i am convinced that it is a great invention: It allows reddit to develop and be a very dynamic system.
Reddit is alive and becoming better every day in its subreddits. The new "todayilearned" and "iama" subreddits are great. Its becoming a little bit like a better usenet.
Hacker News has better discussions, yeah, but reddit has more potential for further development and innovantion...