Players have reported that there is a strange box in the Las Venturas Train Station that looks like a phone booth. Random pedestrians can be seen walking up to it and pressing various buttons. This box is, in fact, a ticket machine for purchasing train tickets, and not a phone booth.
Actual phone booth models exist and can be found within the game. However, they have no mythical properties.
Players have also said that there are various strange megaphones or stereo devices that are located in parts of El Castillo del Diablo and the rest of Bone County. These devices resemble small megaphones or loudspeakers, connected to a small box with an antenna. These megaphones are attached to a post standing upright from the ground. The megaphones are used in the mission Interdiction, in which Mike Toreno relays messages to CJ through the speakers. Strangely, these megaphone devices remain in these locations throughout the whole game, even outside of the mission Interdiction.
In the Mojave desert, there used to be an actual phone booth owned by Pacific Bell, which was located between interstate 40 and 15. It was later removed in the year 2000 by the National Parks services.
In the Glamis sand dunes, near Imperial Valley, located in between two sand dunes and a tree, there used to be a working water fountain. This was removed sometime around 2006-2007. This could also possibly be inspiration for the myth.