Apollo 13 has some great hacker scenes. It has, in fact, my favorite hacker moment from any movie. "We gotta find a way to make this [holds up square peg] fit into the hole for this [holds up round peg] using nothing but that [points to random assortment of crap that they know is on board].": http://www.youtube.com/watch?v=rNDuGuerpf8
Another space/hackish movie would be "The Dish" about the Australian engineers in charge of one the (of course) dishes used to communicate with Apollo 11. Cliffhanger scene: the dish goes out of alignment for some reason and they need to scramble to regain contact in time to televise the moon landing.
And of course there's always "The Right Stuff".