Apparently, a committee in Japan is lobbying for a return to the traditional sake bottle.

The squid skins dry in the sun, stuffed with rice or grains to create the bottle shape. Once fully dried, warm sake is poured into the squid bottle to create a distinct squid-infused Sake flavour. Bottles can be used 4 or 5 times before being eaten.

Technically, these probably aren't "skins." The skin of a squid is a thin, delicate covering that wouldn't hold up well to this sort of treatment. My guess is that they're using the whole mantle--the muscular body of the squid, which is usually turned in calamari rings.

Also, the clause in the second sentence produces an interesting, if puzzling, mental image of "warm dried sake."

Ewww.

(Thanks to Lou Z for the tip.)