Mousou Dairinin, NHK ni Youkoso! Recommendations
Human failures, suicidal tendencies, conspiracy theories and black humor. Oh and both anime have characters who hallucinate ;-)
Both series has an interesting cast of characters dealing with the darker themes of the Japanese culture.
There's also that confusing and mysterious atmosphere going on in both anime(s) that keeps the viewers from predicting what's next. Strange plots forms strange delusions making these two series unique little gems.
Both focus on themes of human failure and living on the edge of depression or paranoia among other things, both showing some parts of the world in a distorted way created by the human mind (Hallucination). However presented differently, with NHK focusing primarily on 1 persons experinces, whereas Paranoia Agent is a little more broad and is a lot more metaphoric with its meaning.
Both feature an internal struggle, namely that of pressure (primarily to succeed etc). Each has a solution of sorts
Although different in some aspects (different vibe, presentation, atmosphere), NHK for some reason reminds me a lot of PA. Mostly for its looking into everyday life, and things that we consider real just so we could avoid really doing and living. And I don't mean just conspiracies (I'd actually argue those *are* to a certain extent real), but our fear of the outside, or, taking the responsibility and blame for our actions.
To repeat gloomlp: "Both focus on themes of human failure".