Densha Otoko

Densha Otoko (literally Train Man) is a story of a young otaku (basically a super-nerd who lives for stuff in Akihabara) who saves a young woman from a drunken passenger on a train. A relationship blossoms over time between them (starting with just casual outings and eventually ending with a proclamation of love), and the whole time Densha Otoko (the aforementioned otaku) consults a webboard (2ch if that means anything to you) for advice on how to change from the single, awkward otaku into a man who can interest and date the beautiful young woman.

Sorry about the lack of English subs for this video. This is the only video on Youtube of the ending. The English subs would give it a lot more meaning, although you can still get some idea from just the footage.

EDIT: I edited this to add in the fact that Densha Otoko is based on a true story of something that actually happened (I think in 2004, but I need to double check on the date). The posts on 2ch are archived and an English translation is available online. I was actually interested enough in the series that I bought an English translation of a book that compiles all of the posts.