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Gordon R. Meyer
Humor in warnings
There are a couple of reasons why humor in technical publications is so rare. Firstly, it's very hard to pull off. Secondly, tech writers as a whole are humorless, at least about their own profession. Due to the scarcity, jokes in documentation make a fine thing to collect,
Here's one to get you started. In a tech support article about SyncServices, user are warned to avoid a key directory as if it were a swarm of angry bees.
See also Firefox Attempts Humor.