One of many in-jokes spawned by Lucasarts' Monkey Island series , first uttered by Guybrush Threepwood in the first game, The Secret of Monkey Island. It was also revealed to be a true statement a little later on in this game, in possibly the only situation where one could 'lose' the game. Guybrush, it would appear, cannot hold his breath for 10 minutes and one second. QED.
Unlike some adventure games, in which daft comments such as this were just that, this particular quote has stuck with the series through each sequel (At least, it might do. I only have the first two games in the series. /msg me if you know to the contrary).
Spare a thought for poor Guybrush whenever you should see (or hear, à la Monkey Island 3 and 4) it.