Have you found yourself a...goldfish?

After watching Mycroft and Sherlock's hilarious operation game and interesting ensuing conversation in the first episode of season 3, there's an implication that Sherlock actually *gasp* has always wanted to have friends. It's implied throughout the series that he's only really isolated himself because of the teasing his classmates gave him (Sebastian in the Blind Banker, etc.) for being insanely smart, because even though he always goes off about being 'annoyed' and 'bored' by ordinary people, he certainly goes out of his way to spend time with John and Molly, and to a lesser extent, Lestrade and Mrs. Hudson. Considering that Mycroft treated him like an idiot when they were very small up until they went to school, he must have identified with normal kids much more than Mycroft, and thus probably always wanted a best friend like John, even if it was only subconscious. Consider that Sherlock has actually started verbally referring to himself as John's best friend in the third episode.

DEM FEELS