We've heard this sound before (think Star Wars), and I've never tried to create it but have wondered about how it is done. Then I heard it again today here and stumbled upon one person's explanation:
"That's not ring modulation. It's Single SideBand Suppressed Carrier Amplitude Modulation, or SSB. Essentially, take an AM signal, cut it in half and remove the carrier. This means it takes up about half the spectrum and is still perfectly understandable, if not exactly broadcast quality. When receiving the signal, the radio reinserts the carrier and demodulates, resulting in that hollow sounding voice coming from the speakers." [seanc0x0 from BoingBoing]
Has anyone out there successfully created this sound before? Would love to hear your examples.