Probably been mentioned already, but Dr. Gregory House from House MD. Cutty & Wilson did breifly touch on it in one episode, but then dismissed it, but I think it explains pretty much all the interesting parts of his personality.
I'd probably say Dr. Artz from Lost as well. The way he'd get so excited about things that no one around him had any interest in, as well as the way he'd take any dismissal of his abilities deeply personaly felt extremly familiar.
Also, possibly Rimmer from Red Dwarf. His obsession with military history and stratagy, his inability to handle social interaction, his apparent contempt for his peers, his stunted sense of humor, and the fact that dispite being intelegent and always trying his hardest things don't quite go the way he wants are all things Ive felt/experienced at various times in my life.