v. to inject a nerdy reference into a serious and/or unrelated event or thread of conversation, thereby hijacking the tone of the event and making it geekier
He completely nerdsharked the wedding when he started reciting the "mahwage" scene from Princess Bride.
A phenomenon resulting from an attempt to pass off a fallacious story as factual, only to subsequently have the story proven wrong, resulting in exhibited defensiveness, bitterness and embarrassment on the part of the teller of said false story.
The term was derived from the following thread (created by a poster names "nerdster") on the NC State message boards:
http://mbd.scout.com/mb.aspx?s=178&f=2535&t=2721704
Note the weak attempts at insulting those who are laughing at the expense of him having "nerdstered" himself throughout the thread.