"Blade Runner" well worth any number of viewings; it's one of the only few believable future scenaria, available on 70 mm. And it is crammed with psychological accuracy, and an AI that understands the universe!
Phoenix will point out 2001, of course, and i agree, but i just watched it again lately, and was somewhat disappointed (i think my memory was overly enhanced, and the special effects have been copied so many times by 'wannabe' Stanley Kubricks, that it now looks dated).
Actually anything worth doing once, is worth doing twice (or every night, depending upon one's stamina
(and the 'titles' available))!