Unlike a conventional spacecraft, which would be navigated on the basis of signals sent to and from ground controllers, Deep Space 1 is programmed to make its own left-right, up-down decisions on data from sensors that look at the stars to track position and guide course changes.

CNN: Spacecraft set for risky asteroid flyby

Scientists suggest that olfactory signals might someday form the basis of new treatments for anxiety and post-traumatic stress disorders.

WSJ: Why Children Have More Control of Their Dreams

Warnings to users (perhaps at certain times and locations), initial authentication, background check requirements, reporting and logging pickup location information and details as to which drivers saw which passenger signals, as well as logging all driver locations on an ongoing basis are some initial suggestions.

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