Free Beer sale on the Isummit 2008 illustrates "Free as in freedom, not free as in free beer": recipe and label shared openly under CC BY-SA ("Free as in freedom") but not gratis ("free as in free beer") as the beer is sold for 500 yen.
In English, the word free has two meanings, which are very different from each other:
Free can mean, that there is no cost associated with it, that something does not cost any money.
Free can also mean, that something is related to freedom.