The most fun I've had using social engineering was to get access to a database that the pukes in the home office had locked up. Our boss' boss wanted access to the raw data, but they wouldn't give it to us. My colleague and I tag teamed them to figure out which server it was on and the names of the files, then he was able to break into it. The boss was very pleased to be able to provide the data as real-time on his boss' dashboard. Christmas bonuses all around.