Solaris

I thought this film was relevant to what we're thinking about: A psychologist is sent to a space station to investigate a strange but unspecified phenomena. When he arrives he finds that some kind of planetary consciousness is producing doubles of deceased people from the memories of the Space Station's crew. He's confronted with a replica of his dead wife, and struggles with whether to destroy"it" or indulge in the illusion of her presence.

There's a remake from I think 2002. I havn't seen it, but the original is beautiful -- amazing image quality, and there's a pacing and a space given to the movie that is really important that you don't get in more recent films. Things are really given time -- definitely worth watching.