SAN FRANCISCO, Apr 1: Google Inc, getting a headstart on the annual tradition of April Fools’ pranks, released a YouTube clip on Sunday declaring that the world’s most popular video website will shut down at the stroke of midnight. The three-minute video intended as a gag – a montage of clips and cameos from viral video stars like David Devore from “David after the dentist” – describes how the website will wind down as some 30,000 technicians begin to trawl through 150,000 clips, to select the world’s best video. (agencies)