Kiyoshi Kurosawa's "Kairo"

Just watched the 2001 Japanese version of "Pulse", which has been recently remade (probably poorly) for the American audience . The original is not the most frightening of horror films, but it manages to wrap two of the most disturbing trends in modern Japanese culture (Hikikomori or "social withdrawl" and mass suicide) into a remarkable existential ghost story. Alienation and loneliness are the real horrors of the film, pushing society to total collapse. Definitely recommended.

Matt Bailey lays out a succinct survey of the cultural issues at play in the film at notcoming.com
Maggie Jones wrote a fantastic piece on Hikkomori for the New York Times Magazine.