Knight and Day was pretty good id probally give it a 7.
My underrated movies(ones that imdb lists under 7):
Sky Captain and the World of Tomorrow
Bunraku
The League of Extraordinary Gentlemen
Hansel & Gretel: Witch Hunters
Hellboy
Lemony Snicket's A Series of Unfortunate Events
The Forbidden Kingdom and pretty much all of Jackie Chans films.
The Brothers Grimm
Oz the Great and Powerful
Monkeybone
What planet are you from?
The Hitchhiker's Guide to the Galaxy
Dragonheart
Contrary to the above list I do watch things other than Science Fiction/Fantasy but everything I've enjoyed/remembered was a 7 or over.