"Tourist Visas" joke
I was once with a tour group visiting the UK. As we filed past the immigration officer (at Heathrow), each one showed his passport, was asked why (s)he was visiting ["Well sir, I'm with this group that is visiting your lovely. .."], and got a one-week tourist visa stamp.
When it was my turn, I said I was going to topple the oppressive government and the entire class system, teach everyone to cook like the French, and free the masses from their servitude, but since I didn't want to stay and experience the ensuing chaos, I might as well get a tourist visa too.
He said, "Normally I'd tell you such a job is rather a large undertaking, and stamp you for two weeks, but I suspect you're kidding," and gave me the same as the rest.
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