8) House Of M
House of M is a storyline which involved both The Avengers and X-Men, and unless Fox and Marvel Studios reach an unexpected deal in time for Phase 4, Kevin Feige and company are going to have to put a slightly different spin on things. The fact that it was set in a world where mutants were the ruling class makes this better suited for a future X-Men movie in all honest, especially as the big twist ending involved the Scarlet Witch wiping away the powers of all but a couple of hundred mutants.
Still, the exploration of an alternate reality where one of The Avengers’ greatest villains – let’s say Kang the Conqueror for argument’s sake – is a concept which would work well on the big screen. Of course, it would be nice if Marvel and Fox could reach a similar deal to what the former did with Sony for Spider-Man, but don’t hold your breath!