In voodoo, one of the more powerful loa. Lord of the crossroads.
In the novel Count Zero by William Gibson, Legba is one of the AIs created by the union of Wintermute and Neuromancer that have infiltrated cyberspace. As Lord Of The Crossroads, he is seen as the loa of communication, and therefore the Net.
Papa Legba also appears in Tim Powers' voodoo/pirate novel On Stranger Tides.