Inglourious Basterds - I have no idea why they spelt it like that, nothing in the film explained it.
i remember reading about that a while back:
The title of the film was inspired by the English title of director Enzo Castellari's 1978 war film, The Inglorious Bastards. When asked for an explanation of the film's title spelling during a news conference at the Cannes Film Festival, Tarantino said, "I'm never going to explain that". When pushed on it, Tarantino would not explain the first u in Inglourious, but said, "The Basterds? That's just the way you say it: Basterds." Tarantino later stated in an interview that the misspelled title is "a Basquiat-esque touch." He further commented on Late Show with David Letterman that Inglourious Basterds is the "Tarantino way of spelling it."
that's on wikipedia so it must be true.