TV.com has a feature on five shows whose fans (were) devoted to keeping their OTP (One True Pairing) together "by any means necessary":
Show: Supernatural
Sinking Ship: The lead actors dare to find real-life love with people other than one another
For some Supernatural fans, shipping extends to the actors involved with the show. That’s right: They take the “b” out of the Jared Padalecki and Jensen Ackles bromance. Far be it from us to judge, but things got out of hand when both leads got engaged. Ackles’ fiancée Danneel Harris got hate-spammed on Twitter, but neither actor was safe: According to some especially crazed fans, Padalecki and Ackles just won’t be happy until they admit their true feelings for each other.
Source: TV.com.