The sound comes from Taskmaster, the British comedy game show in which comedians take on strange and often impossible tasks for points. Alan Davies, the comedian, delivers the wow as a spontaneous reaction, and short reaction clips like this travel well because they work without context. On soundboards and in short-form edits, the moment has been reused as a quick shorthand for amazement, often attached to reveals, monsters, transformations and other eye-catching visuals. Its brevity is part of its staying power, since it can be dropped into almost any clip without slowing it down.