It's hard to imagine a drama or film that involves the internet in quite the same way as Otoko Densha.
The story, as many know, is basically true: In Japan, a shy anime geek tries to save a young woman from being molested by a drunken man in a train. He's almost willing to drop things there, but when an attractive young woman expesses her gratitude, a series of small adventures magnify to colossal ones. That's where his internet chat comes - a network of support he clings to as he tries to wade his way through the uncertain waters of a personal relationship.
A few of the performances here can be a overbaked at times, but Otoko Densha basically a comedy, It's aksi incredibly winning. To add realism, we actually get to read the actual internet posts that the forum members left over the course of the young man's coming of age, including ascii art work left to give him inspiration. There are some deviations from the original plot (some contrived, others extremely funny), but it's hard to recall a dorama that's quite as sweet and touching.
Subtitled versions of the serial are available with a bit of searching, as well as an extensive translation of the original posts.