folding snorkels ?

Having dispensed with a snorkel for diving, I still have the worry in
the back of my mind about being lost at sea, especially in rough
weather. Apparently you can get folding snorkels to put in your pocket
to at least reduce this worry; hopefully never to be used! I've never
seen one in real life, but I recall some bloke on ebay was selling them
a while back, though not now apparently. Anyone used one, or can
suggest a likely looking model or dive-shop which has them ? Or is it a
daft idea. I don't think I've imagined the whole thing.

Cheers

Hywel