quicktime pro does it, but isn't freeware or have a 30 dial trial, but it is pretty cheap. $29.99 its not often you hear the word cheap in a sentence with apple, unless its preceeded by not
its also considerably less trouble than anything i've used to do this before.
But if you want free (its donationware these days)
http://www.radgametools.com/bnkdown.htm