Mr. Gibbs: Then, on the fourth day, he roped himself a couple of sea turtles, lashed ‘em together and made a raft.
Will Turner: He roped a couple of sea turtles.
Mr. Gibbs: Aye. Sea turtles.
Will Turner: What did he use for rope?
Jack Sparrow: [from beside them] Human hair.
[pause]
Jack Sparrow: From my back.

From POTC of course. I copied this from IMDB :)

^{I realise now that my POTC obsession has faded somewhat recently. How odd.}