A line originally used by Lisa Simpson after a psycedelic trip induced by imbibing a handful of water from a theme park ride closely resembling the "its a small world after all" ride at Disney World.

Now used by myself and several acquaintances whenever we don't feel like devoting our attention to someone speaking to us; sometimes because we are actually 'coming down' but more often because we are busy with something else like watching The Simpsons.