Which Scifi Franchises Should Go Head-To-Head Next?

It's sad but true: we'll probably never see another Aliens vs. Predator movie, now that AVP2 failed to set last Christmas on fire. But that doesn't mean Hollywood can't revive some other moribund franchises by forcing them to fight each other. Which classic but struggling universes would you like to see mashed together … » 4/08/08 4:47pm 4/08/08 4:47pm