I love movie posters new and old.
I have an original Empire Strikes Back poster that is folded (probably the only one of any value from my small collection). I haven't been able to find an inexpensive frame for it yet. The size is too big to fit in the movie poster frames that you can purchase off the shelf.
I have the teaser posters to all three Star Wars prequels, the teaser Planet of the Apes Tim Burton remake, the first two Harry Potter teasers, and the Lord of the Rings movie poster (the one that is double sided and the ring is really bright on the reverse side so it would really stand out behind a lighted frame). I also have a promotional poster that was advertised in a magazine (I can't remember which one) for Revenge of the Jedi before they changed the name. I don't know if it is worth anything but it is a nice conversation piece since most people don't know that the name was changed unless you are a big follower of Star Wars.
I also have one Broadway poster which is the original Wicked with the original cast. I imagine that might be worth a little money too.
They are all nice pieces of art and I have to do the same thing of switching them out every so often since they are large and take up a lot of wall space.
"The farther we go, the more the ultimate explanation recedes from us, and all we have left is faith."
~Vaclav Hlavaty