Comics Fans! Which screen versions of comic book characters would you like to see in a movie together?

Freddy and Jason, the Aliens and the Predators. Clic match ups. Seeing how these icons manage share screen time together and make an exciting movie, I think its p time for certain other comic book characters to do a movie together. From Marvel, it would be nice to see the X-Men and Spider Man in a movie together. From DC, it would be nice to see Superman and Batman in a movie and call it, oh, I don't know World's Finest (hint, hint). Better yet Marvel could do a series of movies showing such team-ups and call it Marvel Comics Presents. DC could do a series similar and call it The Brave and The Bold. Each would be based off the comics of the same name. Enough of me brainstorming out loud, what are your ideas for on-screen team-ups?