Well if you don't mind female protagonists, you could try Hayate no Gotoku. It's not serious at all, but the ojou-sama is a child genius who also happens to be a lazy otaku/hikikomori.

Edit: I seem to have somehow forgotten the series that I seem to be suggesting no matter the genre. In Suzumiya Haruhi no Yuutsu, the title character happens to be conveniently and amazingly excellent at everything she does. Despite this, the series is not about her being awesome, but her trying to find interesting things in life (mostly of a supernatural nature). Though I recommend the novel over the manga.

Last edited by imp4ever at 3:31 am, Nov 22 2009

Rival is all I can think of but not sure if you can really call him a genius though, he's unmotivated though.