The song of the laughing kookaburra is one of the most distinctive bird songs in nature, and it's one of the standard sound effects used whenever footage of the Australian bush is shown on film.
That signature kookaburra sound is so unique and such a rich, full-bodied sound that it even sounds cool when it's played in slow motion, as demonstrated in this video of Dacelo the kookaburra shot by his human Connor Margetts.
-Via Laughing Squid