Frivolous lawsuits like this have to be the bane of studios' existence. (Get it? Bane!) In "The Dark Knight Rises," Catwoman (Anne Hathaway) sought a computer program ("Clean Slate") that would wipe all traces of her sordid criminal past from the world's computers. The fictional program was mentioned twice, and viral marketing websites were set up for "Clean Slate" and the fictional company behind it, in order to promote the movie.
In real life, a company called Fortres Grand has a program called "Clean Slate." It resets a computer back to default settings whenever the computer is restarted -- the sort of program that would come in handy on public computers (libraries, hotels, schools) to wipe out user changes to the system, downloaded junk, and personal data.
Fortres Grand sued, claiming that the fictional product created "reverse confusion" with its trademark on "Clean Slate," harming its sales in the process.