I feel like all the best obscure ones were hit on... but here's a list in reverse chronology from 2013>2000 (and one is b4 and out of order). Of somewhat less mainstream Sci-Fi that I enjoyed, even the campy B ones, which had triple A budgets but some how didn't reach mass popularity.
Their all worth a watch on a slow day.
Oblivion <-- is tom cruise more sexy than his leading partner??? IDK... lol )
John Carter <-- fuckin elite old school, done new.
Cloud Atlas <-- I loved this one, for the visuals, and the deep, rich storytelling.
Battleship <-- fun military, kill da aliens. Rock'n'Roll.
Rise of the Planet of Apes <-- best ape movie ever.
Inception
Outlander <- space vikings...
I Am Legend.
Eden Log
Ultraviolet
Ĉon Flux
Cube Zero <-- see also the other "Cube" movie
Cube 2: Hypercube
Cube
Appleseed <- Not GiTS, almost as good
Timeline <- like the book
S1m0ne
Minority Report <-- there's a for real ever-quest joke in this movie
Equilibrium
A.I. Artificial Intelligence
Red Planet <- bad, but FOR MOTHER RUSSIA SPACE AGENCY OF THE USSR YA!
Mission to Mars <- not so bad
I'de also throw
I, Robot up in that mix, be surprised if you haven't seen it already. No it's not the book, but the movie is good, especially if you don't read.