I finished watching this last week and found out the origin of those gif from 4chan with 6-7 people what seems to be laughing in front of their monitor example, http://putfile.com/pic.php?pic=11/32923490285.gif&s=x12
Anyways Densha Otoko is based on a bunch of annoymous post on 2chan (4chan is the sister chan of 2chan but in English) it was about a otaku Tsuyoshi Yamada saving a high class business women nicknamed Hermes, from a drunk on train while coming back home. Apparently the women sended him a thank you gift and they started to meet frequetly. Of course being a Otaku he doesn't know anything about women so with the help of the 2chan message board users they help and give tips to Yamada, it became a really big thing in Japan, a phenomenon, and caught the medias attention and was made into a 12episode tv series.
You can watch it off youtube with their shitty video quality just search for "Densha Otoko" It was entertaining i say, but what i don't like is the music and sometimes the acting done by the actors seems very unnatural. Anyways its about every male otaku's fantansy, so why not watch it.
There have been controversy has to whether or not the story was real, people have said they met the real Densha Otoko but some are skeptical but whatever, it seems like a good watch and maybe a touch of comfort for some of us after watching this. More info on wiki if you wanna read more about it.
Edit: There are specials episodes for Densha like meeting with the actors etc. and one about how many otaku out of 100 will save a women or something like that. Funny stuff.