OnStar uses (500) numbers.
To quote from a puff piece at
OnStar received the Cellular Telecommunications & Internet
Association's (CTIA) first Future Vision Award for great strides in
the areas of data products, software products and end-user
applications. OnStar employees were honored in 1999 with the General
Motors Boss Kettering Award for the first implementation of a national
wireless network using a non-geographic area code (500) to deliver
OnStar mobile communication services.
National Optical Astronomy Observatory/AURA Inc., Tucson AZ USA
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