SatNav
From Jenny Everywhere Wiki
In at least one universe, SatNavs, unbeknownst to most of the population, “not only knew where things were in the current universe but also infinite other universes”. As a result, they “sometimes” told their users to drive off the roads that physically existed in their universe.
As a result of this quirk, Jenny Over-There gained the ability to know where anything in the Multiverse was currently located after an accident at a SatNav factory. (PROSE: The Tribulations of Jenny Over-There)