One of the greatest science fiction movie of all time is without doubt the 1956 classic Forbidden Planet. One of the reasons it was so successful was the oddly futuristic electronic music of Louse and Bebe Barron, true pioneers in electronic music. What's really odd is that NASA's latest recording of radio signals from the Cassini probe around Saturn sounds remarkably like that music. Check it out:
Thanks to Mark, WA8SME for calling my attention to this.
Addendum: Here's the spectrum of the sounds over time (going left to right in time, up in frequency).
Kind of trippy.