Mycroft pretending to be harmless

[dictionary00.livejournal.com]

Anyone know stories where Mycroft pays more than lip service to the "minor government official" cover? When he meets a character for the first time and pretends (successfully) to be just a harmless stuffy bureaucrat. Or self-important politicians treat him like dirt while Mycroft is manipulating them and laughing inside the whole time. Or he gets involved in a crime by accident and it's a huge mess because he likes to keep a low profile. Or...you get the idea. Bonus for scaring someone half to death upon revealing his true power!

Any verse, pairings and gen welcome, though I'm not a big fan of sentimentality from Mycroft. I am a big fan of ambiguous-but-still-good!Mycroft in the BBC verse.