Anyway, the movie Harold & Kumar Go to White Castle was known as Harold & Kumar Get the Munchies in the UK (according to IMDB, at least). I figure the studio assumed that Brits wouldn’t know what a White Castle was.
I understand that the film known in Australia as *Flying High * was called *Airplane * in other parts of the world.
Then there’s the film known in Australia as The Madness of George III, which was re-titled The Madness of King George in the US. Rumour suggests that this was done partially to avoid American audiences mistaking it for a sequel.
In Singapore, Austin Powers: The Spy who Shagged Me was changed to Austin Powers: The Spy who Shioked Me. It’s pronounced shocked and it’s a slang for feeling wonderful or feeling happy.
Harry Potter and the Sorcerer’s Stone (US title) is known as Harry Potter and the Philosopher’s Stone in the non-US anglosphere, following the original book titles.
The British films Quatermass II and Quatermass and the Pit are known as Enemy from Space and Five Million Years to Earth respectively in the US.
Since there seems to be a running hijack with alternate titles in English in non-English speaking countries (which is not what the OP was asking for), I’ll add two US movies that were retitled in France, but with alternate English-language names: